263844

Appears in sequences

• a(n) = Sum_{k = 0..n} binomial(n,k)^4.at n=6A005260
• Triangle read by rows: T(n,m) = number of 3-uniform T_0-hypergraphs with n distinct edges and m vertices(n>=3, 1<=m<=2*n+1).at n=22A093854
• a(n) = Sum_{k=0..2*n} binomial(2*n, k)^4.at n=3A249332
• Square array A(n, k) = Sum_{j=0..n} binomial(n,j)^k, n >= 0, k >= 0, read by antidiagonals.at n=61A309010
• G.f. A(x,y) = lim_{N->infinity} (1 - P(N,x,y))/(2*x)^N, where P(0,x,y) = -y, and P(n+1,x,y) = sqrt(1 - 4*x + 4*x*P(n,x,y)) for n = 0..N-1.at n=49A352093