25104

Appears in sequences

• Numbers n such that f(n), f(n+1) and f(n+2) are prime, f(m)=72*m^2+7.at n=27A121089
• G.f.: x*(1+x+x^2)*(1+6*x+8*x^2+4*x^3-x^4)/((1+x)^2*(1-x)^4).at n=23A147691
• Number of set partitions C'_t(n) of {1,2,...,t} into at most n parts, with an even number of elements in each part distinguished by marks and such that no part contains both 1 and t (each unmarked) or both i and i+1 (each unmarked) for some i with 1 <= i < t; triangle C'_t(n), t>=0, 0<=n<=t, read by rows.at n=44A261319
• Number of parts in all partitions of n with largest multiplicity ten.at n=31A320380
• Number of set-systems covering n vertices, every two of which appear together in some edge (cointersecting).at n=4A327040
• The number of permutations of {(n+1) 1's, (n+1) 2's, ..., (n+1) n's} with the property that k's are equally spaced for k=1..n and the interval of k+1 is less than or equal to the interval of k for k=1..n-1.at n=6A332783
• a(n) = exp(-1/2) * Sum_{k>=0} (2*k - 1)^n / (2^k * k!).at n=8A337038
• a(n) = Sum_{k=0..floor(n/3)} (k+1) * binomial(2*k,2*n-6*k).at n=25A382496