A309296 (1/4) times the sum of the elements of all subsets of [n] whose sum is divisible by four.

0, 0, 0, 1, 4, 14, 42, 112, 288, 720, 1760, 4224, 9984, 23296, 53760, 122880, 278528, 626688, 1400832, 3112960, 6881280, 15138816, 33161216, 72351744, 157286400, 340787200, 736100352, 1585446912, 3405774848, 7298088960, 15602810880, 33285996544, 70866960384

Offset

0,5

Links

Alois P. Heinz, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (6,-12,8).

Formula

G.f.: -x^3*(8*x^5-4*x^4-2*x^3+2*x^2-2*x+1)/(2*x-1)^3.

Mathematica

LinearRecurrence[{6, -12, 8}, {0, 0, 0, 1, 4, 14, 42, 112, 288}, 50] (* Harvey P. Dale, Sep 09 2019 *)

Crossrefs

Column k=4 of A309280.

Sequence in context: A262875 A219867 A295201 * A124616 A335514 A221058

Adjacent sequences: A309293 A309294 A309295 * A309297 A309298 A309299

Keyword

nonn,easy

Author

Alois P. Heinz, Jul 21 2019

Status

approved