A163929 Denominators of the higher order exponential integral constants alpha(2,n).

1, 1, 16, 1296, 20736, 12960000, 4320000, 10372320000, 165957120000, 40327580160000, 40327580160000, 590436101122560000, 590436101122560000, 16863445484161436160000, 2409063640594490880000, 2409063640594490880000

Offset: 1

Author

Johannes W. Meijer & Nico Baken, Aug 13 2009, Aug 17 2009

Keywords

• nonn
• frac

Comments

See A163927 for information about the constants alpha(k,n).

Examples

			alpha(k=2, n=1) = 0, alpha(k=2, 2) = 1, alpha(k=2, 3) = 21/16, and alpha(k=2, 4) = 1897/1296.
		

Crossrefs

Cf. A163928 (numerators).

Formula

alpha(k,n) = (1/k)*Sum_{i=0..k-1} Sum_{p=0..n-1} p^(-2*(k-i))*alpha(i, n) with alpha(0,n) = 1. For this sequence, k = 2 and n >= 1.