A087431 a(n) = 0^n/2 + 2^n*(n^2+n+2)/4.

1, 2, 8, 28, 88, 256, 704, 1856, 4736, 11776, 28672, 68608, 161792, 376832, 868352, 1982464, 4489216, 10092544, 22544384, 50069504, 110624768, 243269632, 532676608, 1161822208, 2524971008, 5469372416, 11811160064, 25434259456

Offset: 0

Author

Paul Barry, Sep 02 2003

Keywords

• easy
• nonn

Comments

Binomial transform of A080335 (with additional leading 1).

Links

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

Programs

Mathematica

LinearRecurrence[{6,-12,8},{1,2,8,28},30] (* Harvey P. Dale, Nov 26 2015 *)

Formula

a(n) = 2*A007466(n) for n >= 1.

G.f.: (1-4*x+8*x^2-4*x^3)/(1-2*x)^3. - Colin Barker, Mar 18 2012