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69
Answers
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24
The Matrix-Tree Theorem without the matrix
Aug 22 '11 at 18:40
17
A particular combinatorial proof of Wilson's theorem
Feb 2 '11 at 3:48
15
Show that this ratio of factorials is always an integer
May 12 '13 at 15:00
14
Combinatorial Morse functions and random permutations
Jul 9 '14 at 16:27
14
Combinatorial meaning of the functional equation for logarithm
Nov 16 '12 at 17:50
14
Extremely messy proofs
Jan 14 '11 at 16:42
13
Number of closed walks on an $n$-cube
Aug 1 '11 at 15:50
13
Use of everywhere divergent generating functions
Nov 13 '10 at 18:50
13
formal power series convergence
Nov 11 '10 at 3:53
12
Combinatorial identities
Nov 27 '13 at 16:48
12
The combinatorial interpretation of an identity found in “Primes in tuples I”
Nov 22 '13 at 4:49
11
Exponential of a specific hypergeometric series
Feb 5 '14 at 14:38
11
“MultiCatalan numbers”
Oct 14 '13 at 17:58
11
The proportion between permutations and derangements.
Jun 16 '13 at 19:58
11
Interpolating a sum of binomial coefficients using a sin function
Oct 11 '12 at 18:06
11
Number of integer combinations x_1 < … < x_n ?
Jan 18 '12 at 15:58
9
power series of the reciprocal… does a recursive formula exist for the coefficients.
Jan 26 '11 at 21:22
8
Identity for Power Series and Binomial Coefficients
Jan 26 at 22:22
8
Sign of coefficients
Apr 29 '13 at 13:52
8
Counting card distributions when cards are duplicated
Feb 18 '11 at 17:40
7
Computer package for representation theory of the symmetric group
May 16 '12 at 22:10
7
Number of Dyck paths with prescribed number of edges
Feb 20 at 17:59
7
A recurrence relation on Catalan numbers
Dec 26 '14 at 21:54
7
Counting chains of inclusions
May 30 '14 at 19:25
7
Is there an interesting species whose generating function gives the zigzag numbers?
Mar 26 '14 at 0:14
7
Identifying a special function from its power series
Nov 6 '13 at 17:48
7
The number of lattice paths below y=n/m x for gcd(m,n) = 1
Jun 9 '13 at 21:09
7
Faa di Bruno's formula for inverse functions ?
May 31 '12 at 20:15
7
Sum of products of exponentials and polynomials
Nov 22 '11 at 16:02
7
Implications of a relation on algebraic numbers
Sep 3 '11 at 23:36
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