-6886
domain: Z
Appears in sequences
- Expansion of 1/((1-x)*(1+x+2*x^2-x^3)).at n=20A077911
- G.f. A(x,y) satisfies: Sum_{n=-oo...+oo} (x^n + y)^n = exp( (1-y) * A(x,y) ) / (1-y), where A(x,y) = Sum_{n>=1} x^n/n * Sum{k=0..n-1} T(n,k)*y^k, written here as a flattened triangle of coefficients T(n,k) read by rows.at n=26A321600
- a(n) = Sum_{k=0..floor(n/4)} (-1)^k * binomial(n-1-3*k,n-4*k) * binomial(2*k,k).at n=24A360315