18404

Appears in sequences

• a(n) = Sum_{k=0..floor(n/2)} T(n-k,k), T given by A026736.at n=20A026746
• Non-balanced numbers in A015771.at n=30A078549
• a(n) = Product_{i=n..n+4} A000045(i) mod Sum_{i=n..n+4} A000045(i).at n=20A348914
• Triangle of coefficients of the primitive Eulerian polynomials of type D T(n,k) (n >= 2, 1 <= k <= n) read by rows.at n=22A363935
• Triangle read by rows: T(n,k) is the number of embeddings on the sphere of 2-connected homeomorphically irreducible planar graphs with n nodes and k faces, k=4..2n-4.at n=44A378075
• G.f. A(x) satisfies A(x) = 1 + x*abs( 1/A(x) )^2.at n=15A380708
• a(n) = Sum_{k=0..n} binomial(k+3,3) * binomial(2*k,2*n-2*k).at n=7A382470