A309296 - OEIS

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

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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.