A357545 Central terms of triangle A357541: a(n) = A357541(2*n,n).

1, 120, 38966400, 335872728576000, 23676862831649280000000, 7884265450248813494550528000000, 9001018126678397460727568113336320000000, 28542885018291526761600709316931461578752000000000, 216619327660243309425808505300579182909935738421248000000000

Offset: 0

Author

Paul D. Hanna, Oct 10 2022

Keywords

• nonn

Comments

Also equals central terms of triangle A357542: a(n) = A357542(2*n,n).

Crossrefs

Cf. A357541, A357542.

Programs

PARI

{A357541(n, k) = my(S = serreverse( intformal( 1/((1 + x^3)^2*(1 + r^3*x^3)^2 +O(x^(3*n+3)) )^(1/3) )) );
(3*n)!*polcoeff( polcoeff((1 + S^3)^(1/3), 3*n, x), 3*k, r)}
for(n=0, 15, print1( A357541(2*n, n), ", "))