A181889 Bisection of A181888.

0, 64, 784, 4368, 16368, 48048, 119392, 262752, 527136, 983136, 1728496, 2894320, 4651920, 7220304, 10874304, 15953344, 22870848, 32124288, 44305872, 60113872, 80364592, 106004976, 138125856, 177975840, 226975840, 286734240, 359062704, 445992624, 549792208, 672984208, 818364288, 989020032, 1188350592, 1420086976, 1688312976, 1997486736, 2352462960, 2758515760, 3221362144, 3747186144

Offset

1,2

Comments

These are scaled central factorial numbers.

Links

Paolo Xausa, Table of n, a(n) for n = 1..10000

Index entries for linear recurrences with constant coefficients, signature (7,-21,35,-35,21,-7,1).

Formula

G.f.: -16*x^2*(4+21*x+14*x^2+x^3)/(x-1)^7. - R. J. Mathar, May 18 2026

a(n) = 2*n*(n-1)*(2*n+1)*(2*n-1)*(5*n+6)*(n+1)/45. - R. J. Mathar, May 18 2026

Mathematica

A181889[n_] := 2*(n-1)*n*(n+1)*(2*n-1)*(2*n+1)*(5*n+6)/45;
Array[A181889, 40] (* Paolo Xausa, May 22 2026 *)

Crossrefs

A bisection of A181888. Cf. A001823.

Sequence in context: A317610 A264260 A190532 * A236182 A164280 A232001

Adjacent sequences: A181886 A181887 A181888 * A181890 A181891 A181892

Keyword

nonn,easy

Author

N. J. A. Sloane, Feb 01 2011

Status

approved