A275636 a(n) = (3^n-1)*(3^n+3)/3!.

0, 2, 16, 130, 1120, 9922, 88816, 797890, 7176640, 64576642, 581150416, 5230235650, 47071766560, 423644836162, 3812800336816, 34315193465410, 308836712490880, 2779530326324482, 25015772678640016, 225141953332919170, 2026277577671749600

Offset

0,2

References

Turner, Zachary J., Bryson W. Finklea, and Terri Moore. "Combinatorial Approaches to Minimal Zero Sequences of Finite Abelian Groups, and a Surprising Connection." Preprint, Jan 09 2004.

Links

Colin Barker, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (13,-39,27).

Formula

From Chai Wah Wu, Aug 09 2016: (Start)

a(n) = 13*a(n-1) - 39*a(n-2) + 27*a(n-3) for n > 2.

G.f.: 2*x*(5*x - 1)/((x - 1)*(3*x - 1)*(9*x - 1)). (End)

a(n) = (2*3^n+9^n-3)/6. - Colin Barker, Aug 10 2016

Crossrefs

Sequence in context: A360321 A074623 A323946 * A002576 A037727 A037622

Adjacent sequences: A275633 A275634 A275635 * A275637 A275638 A275639

Keyword

nonn,easy

Author

N. J. A. Sloane, Aug 09 2016

Status

approved