20546

Appears in sequences

• G.f.: Sum_{n >= 1} x^n/(1-x^n)^5.at n=24A073570
• Number of peaks at even levels in all hill-free Dyck paths of semilength n+2 (a hill in a Dyck path is a peak at level 1).at n=8A114590
• A Fine number related number triangle.at n=46A124392
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, -1, 1), (-1, 1, 0), (1, 0, 0), (1, 1, -1)}.at n=11A148059
• Semiprimes in A007504 (the sum of first n primes).at n=25A189072
• Number of 3n-length 8-ary words, either empty or beginning with the first letter of the alphabet, that can be built by repeatedly inserting triples of identical letters into the initially empty word.at n=4A218478
• Composite numbers n such that Sum_{k = 0..n} (-1)^k * C(n,k) * C(2*n,k) == -1 (mod n^3) (see A234839).at n=30A268303
• a(n) = Sum_{d|n} d^(2*(n/d - 1)).at n=15A308692
• a(n) = Sum_{d|n} (-1)^(n/d-1) * binomial(d+3,4).at n=24A366814