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Combinatorics:
Counting,
Recurrence relations,
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Recurrence Relation SelfDoubt
What will be solution of recurrence relation if roots are like this: r1=2, r2=2, r3=2, r4=2 is this the case of repetitive roots?
asked
May 14
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aditi19
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relations
recurrence
recurrenceeqation
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Rosen 7e Exercise 8.2 Questionno26 page no525 Recurrence Relation
What is the general form of the particular solution guaranteed to exist of the linear nonhomogeneous recurrence relation $a_n$=$6a_{n1}$$12a_{n2}$+$8a_{n3}$+F(n) if F(n)=$n^2$ F(n)=$2^n$ F(n)=$n2^n$ F(n)=$(2)^n$ F(n)=$n^22^n$ F(n)=$n^3(2)^n$ F(n)=3
asked
May 14
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Combinatory
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aditi19
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24
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kennethrosen
discretemathematics
#recurrencerelations
recurrence
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0
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3
Rosen 7e Exercise8.2 Question no23 page no525 Recurrence Relation
Consider the nonhomogeneous linear recurrence relation $a_n$=$3a_{n1}$+$2^n$ in the book solution is given $a_n$=$2^{n+1}$ but I’m getting $a_n$=$3^{n+1}2^{n+1}$
asked
May 13
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Combinatory
by
aditi19
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17
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kennethrosen
discretemathematics
#recurrencerelations
recurrence
0
votes
2
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4
#probability(self doubt)
An automobile showroom has 10 cars, 2 of which are defective. If you are going to buy the 6th car sold that day at random, then the probability of selecting a defective car is??
asked
May 13
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Combinatory
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G Shaheena
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#probability
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5
ISI2018MMA26
Let $C_i(i=0,1,2...n)$ be the coefficient of $x^i$ in $(1+x)^n$.Then $\frac{C_0}{2} – \frac{C_1}{3}+\frac{C_2}{4}\dots +(1)^n \frac{C_n}{n+2}$ is equal to $\frac{1}{n+1}\\$ $\frac{1}{n+2}\\$ $\frac{1}{n(n+1)}\\$ $\frac{1}{(n+1)(n+2)}$
asked
May 11
in
Combinatory
by
akash.dinkar12
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40.5k
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99
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isi2018
engineeringmathematics
discretemathematics
generatingfunctions
0
votes
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6
ISI2018MMA10
A new flag of ISI club is to be designed with $5$ vertical strips using some or all of the four colors: green, maroon, red and yellow. In how many ways this can be done so that no two adjacent strips have the same color? $120$ $324$ $424$ $576$
asked
May 11
in
Combinatory
by
akash.dinkar12
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40.5k
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20
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isi2018
engineeringmathematics
discretemathematics
permutationsandcombinations
0
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7
A first course in probability by Sheldon Ross
What are the relevant chapter of probability by sheldon ross to study for gate? I think whole syllabus is within chapter 5,Should i study everything upto chapter 5 or there are some topics that can be skipped.
asked
May 8
in
Combinatory
by
souren
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21
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21
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probability
sheldonross
0
votes
2
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8
ISI2019MMA27
A general election is to be scheduled on $5$ days in May such that it is not scheduled on two consecutive days. In how many ways can the $5$ days be chosen to hold the election? $\begin{pmatrix} 26 \\ 5 \end{pmatrix}$ $\begin{pmatrix} 27 \\ 5 \end{pmatrix}$ $\begin{pmatrix} 30 \\ 5 \end{pmatrix}$ $\begin{pmatrix} 31 \\ 5 \end{pmatrix}$
asked
May 7
in
Combinatory
by
Sayan Bose
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6.9k
points)

2.7k
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isi2019
engineeringmathematics
discretemathematics
permutationsandcombinations
0
votes
2
answers
9
ISI2019MMA20
Suppose that the number plate of a vehicle contains two vowels followed by four digits. However, to avoid confusion, the letter ‘O’ and the digit ‘0’ are not used in the same number plate. How many such number plates can be formed? $164025$ $190951$ $194976$ $219049$
asked
May 7
in
Combinatory
by
Sayan Bose
Loyal
(
6.9k
points)

280
views
isi2019
engineeringmathematics
discretemathematics
permutationsandcombinations
0
votes
1
answer
10
ISI2019MMA4
Suppose that $6$digit numbers are formed using each of the digits $1, 2, 3, 7, 8, 9$ exactly once. The number of such $6$digit numbers that are divisible by $6$ but not divisible by $9$ is equal to $120$ $180$ $240$ $360$
asked
May 6
in
Combinatory
by
Sayan Bose
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6.9k
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172
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isi2019
engineeringmathematics
discretemathematics
permutationsandcombinations
0
votes
1
answer
11
ISI2019MMA2
The number of $6$ digit positive integers whose sum of the digits is at least $52$ is $21$ $22$ $27$ $28$
asked
May 6
in
Combinatory
by
Sayan Bose
Loyal
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6.9k
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212
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isi2019
engineeringmathematics
discretemathematics
permutationsandcombinations
0
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12
Rosen 7e Recurrence Relation Exercise8.1 Question no25 page no511
How many bit sequences of length seven contain an even number of 0s? I'm trying to solve this using recurrence relation Is my approach correct? Let T(n) be the string having even number of 0s T(1)=1 {1} T(2)=2 {00, 11} T(3)=4 {001, ... add 0 to strings of length n1 having odd number of 0s T(n)=T(n1) Hence, we have T(n)=2T(n1)
asked
Apr 29
in
Combinatory
by
aditi19
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34
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kennethrosen
discretemathematics
permutationsandcombinations
#recurrencerelations
recurrence
0
votes
1
answer
13
Rosen 7e Exercise8.1 Question no10 Page no511
Find a recurrence relation for the number of bit strings of length n that contain the string 01.
asked
Apr 28
in
Combinatory
by
aditi19
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3.5k
points)

33
views
kennethrosen
discretemathematics
combinatory
#recurrencerelations
recurrence
+1
vote
1
answer
14
Pgee 2013
You have a box containing 10 black and 10 blue socks.What is the minimum number of times you need to pull out so that you have a pair of the same color?
asked
Apr 22
in
Combinatory
by
Winner
(
269
points)

84
views
iiithpgee
0
votes
0
answers
15
Kenneth H Rosen 7th edition
Please see example 6. l am not getting the mathematical insight. Can anyone please tell how they are arriving at the answer.
asked
Apr 21
in
Combinatory
by
Psnjit
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211
points)

40
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kennethrosen
discretemathematics
permutationsandcombinations
+2
votes
1
answer
16
Rosen 7e Exercise6.5 question 45.b page 433
How many ways can n books be placed on k distinguishable shelves if no two books are the same, and the positions of the books on the shelves matter?
asked
Apr 16
in
Combinatory
by
aditi19
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3.5k
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154
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kennethrosen
discretemathematics
permutationsandcombinations
combinatory
0
votes
1
answer
17
Madeeasy Discrete Maths notes
How many 5 letter word possible having atleast 2 a's ?
asked
Apr 9
in
Combinatory
by
Prakhar Garg
(
71
points)

59
views
madeeasynotes
discretemathematics
permutationsandcombinations
0
votes
1
answer
18
Self doubt
How is the problem.. Distribute 5 toys such that each of 3 child get atleast 1 Different from sum of 3 no. X+y+z=5 such that each digit >= 1. Plz explain ?
asked
Apr 4
in
Combinatory
by
Manoj Kumar Pandey
(
179
points)

56
views
permutationsandcombinations
0
votes
0
answers
19
Combinatorics
There are 6n flowers of one type and 3 flowers of second type, total no. Of garlands possible?
asked
Apr 2
in
Combinatory
by
Manoj Kumar Pandey
(
179
points)

15
views
permutationsandcombinations
0
votes
0
answers
20
General Query: Self doubt(Math+Automata)
Can somebody explain What is identity permutation?
asked
Apr 1
in
Combinatory
by
srestha
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114k
points)

23
views
discretemathematics
finiteautomata
0
votes
0
answers
21
website
There is 4 coins 1 paisa, 5 paise, 10 paise, 25 paise using these coins we have to make 50 paisa how many combination can we make ?
asked
Mar 31
in
Combinatory
by
Cristine
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1.6k
points)

26
views
permutationsandcombinations
0
votes
0
answers
22
Allen Career Institute: Discrete Mathematics
A certain software was being tested by using error seeding strategy in which $22$ errors were seeded. $14$ of seeded errors were detected apart from $140$ unseeded errors when the code was tested using the complete test suit. Calculate the estimated no. of undetected errors in the code after complete testing _____
asked
Mar 22
in
Combinatory
by
srestha
Veteran
(
114k
points)

29
views
discretemathematics
permutationsandcombinations
+1
vote
1
answer
23
Model Question IISc CDS CS Written Test Sample question
Anand is preparing a pizza with 8 slices, and he has 10 toppings to put on the pizza. He can put only one topping on each slice but can use the same topping on zero or more slices. In how many unique ways can he prepare the slices so that the same topping is not used in adjacent slices?
asked
Mar 11
in
Combinatory
by
Chaitrasj
Junior
(
955
points)

176
views
iisc
cds
0
votes
1
answer
24
ACE Test Series: Generating Function
The generating function of the sequence $\left \{ a_{0},a_{1},a_{2}..........a_{n}………...\infty \right \}$ where $a_{n}=\left ( n+2 \right )\left ( n+1 \right ).3^{n}$ is $a)3\left ( 1+3x \right )^{2}$ $b)3\left ( 13x \right )^{2}$ $c)2\left ( 1+3x \right )^{3}$ $d)2\left ( 13x \right )^{3}$
asked
Mar 8
in
Combinatory
by
srestha
Veteran
(
114k
points)

59
views
generatingfunctions
discretemathematics
+2
votes
1
answer
25
Rosen 7e, Advance Counting techniques , Question 6.f
Find the generating function for the sequence $\left \{ a_n \right \} where $ $a_n = \Large \binom{10}{n+1} $ ... $\Large \color{red}{ \frac{( 1+x )^{10}  1}{x} }$ Please verify
asked
Mar 7
in
Combinatory
by
Mk Utkarsh
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(
35.4k
points)

41
views
kennethrosen
discretemathematics
generatingfunctions
0
votes
1
answer
26
Rosen Ex.6.1
Find a recurrence relation for the number of ways to lay out a walkway with slate tiles if the tiles are red, green, or gray so that no two red tiles are adjacent and tiles of the same color are considered indistinguishable
asked
Mar 3
in
Combinatory
by
himgta
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(
4k
points)

31
views
0
votes
0
answers
27
Pg 345 Question 23, 6th Edition KH Rosen
How many strings of three decimal digits do not contain the same digit three times? have exactly two digits that are 4s? I know question is easy but the answer is not matching with the one given over here Please someone verify.. Does the word “string” mean that we can take 0 as the first digit as well?
[closed]
asked
Feb 27
in
Combinatory
by
MiNiPanda
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22k
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45
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kennethrosen
discretemathematics
+1
vote
1
answer
28
Rosen example 12 Ch 5.2
Show that every sequence of $n^2$+1 distinct real numbers contains a subsequence of length n+1 that is either strictly increasing or strictly decreasing.
asked
Feb 24
in
Combinatory
by
himgta
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(
4k
points)

49
views
0
votes
2
answers
29
Kenneth Rosen Example 9 Ch.5.2
Suppose that a computer science laboratory has 15 workstations and 10 servers. A cable can be used to directly connect a workstation to a server. For each server, only one direct connection to that server can be active at any time. We ... 't understand this part. How is it concluded that remaining nine servers are insufficient when at most 59 connections are used?
asked
Feb 23
in
Combinatory
by
himgta
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(
4k
points)

70
views
0
votes
1
answer
30
Self Doubt
From a group of 5 woman and 7 man we have to select a committee consisting of 2 woman and 3 men. Find the total number of ways to select such committed if (1 and 2 are a separate question) 1. Four man refuse to be in the same committee 2. 2 woman refuse to be in the same committee.
asked
Feb 8
in
Combinatory
by
smsubham
Loyal
(
9.3k
points)

67
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counting
permutationsandcombinations
discretemathematic
discretemathematics
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