A171552 a(n)=2^n*floor((5-2n)/3).

1, 2, 0, -8, -16, -64, -192, -384, -1024, -2560, -5120, -12288, -28672, -57344, -131072, -294912, -589824, -1310720, -2883584, -5767168, -12582912, -27262976, -54525952, -117440512, -251658240, -503316480, -1073741824, -2281701376

Offset

0,2

Comments

Hankel transform of A131428.

Links

Table of n, a(n) for n=0..27.

Index entries for linear recurrences with constant coefficients, signature (2,0,8,-16).

Formula

G.f.: (1-4x^2-16x^3)/((1-2x)(1-8x^3)).

Crossrefs

Sequence in context: A120559 A120555 A128063 * A087205 A319196 A308536

Adjacent sequences: A171549 A171550 A171551 * A171553 A171554 A171555

Keyword

easy,sign

Author

Paul Barry, Dec 11 2009

Status

approved