A107904 - OEIS

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A107904

Expansion of (1+6x)/(1-12x^2).

1, 6, 12, 72, 144, 864, 1728, 10368, 20736, 124416, 248832, 1492992, 2985984, 17915904, 35831808, 214990848, 429981696, 2579890176, 5159780352, 30958682112, 61917364224, 371504185344, 743008370688, 4458050224128

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OFFSET

0,2

COMMENTS

Fourth binomial transform is A107903.

LINKS

Table of n, a(n) for n=0..23.

Index entries for linear recurrences with constant coefficients, signature (0,12).

FORMULA

a(n) = ((1+sqrt(3))*(2*sqrt(3))^n + (1-sqrt(3))*(-2*sqrt(3))^n)/2.

a(2n) = 12^n, a(2n+1) = 6*12^n.

a(n) =2^n*A108411(n+1). - R. J. Mathar, Aug 15 2023