A379555 Row products of the triangle A330613.

1, 1, 10, 312, 19800, 2112320, 339721200, 76736721600, 23161613673856, 9002333397657600, 4378779743334796800, 2605462349704907264000, 1861650500340096385920000, 1572904258939213777572323328, 1551130967414603865237595648000, 1765646154517023983944233381888000, 2297658475440816396798100972400640000

Offset

0,3

Links

Table of n, a(n) for n=0..16.

Formula

a(n) = (1 - 2*n)^(n-1)*(1 - 2*n + 2*n^2)*Pochhammer(-2*(n - 1)^2/(2*n - 1), n - 1).

a(n) ~ C*2^n*exp(3/(8*n)-n)*n^(2*n), where C = sqrt(2/e) = A227514.

Mathematica

a[n_]:=(1-2n)^(n-1)(1-2n+2n^2)Pochhammer[-2(n-1)^2/(2n-1), n-1]; Array[a, 17, 0]

Crossrefs

Cf. A227514, A330613.

Sequence in context: A228188 A041425 A217505 * A222972 A119297 A259066

Adjacent sequences: A379552 A379553 A379554 * A379556 A379557 A379558

Keyword

nonn

Author

Stefano Spezia, Dec 25 2024

Status

approved