OFFSET
0,2
LINKS
FORMULA
a(n) = 2^n * A004526(n+2).
From Arkadiusz Wesolowski, Dec 28 2011: (Start)
a(n) = 2^(n-2)*(2*n + 3 + (-1)^n).
G.f.: 1/((1 - 2*x)*(1 - 4*x^2)). (End)
G.f.: G(0)/(1-x), where G(k)= 1 + 2*x*(k+1)/(k+2 - 2*x*(k+2)*(k+3)/(2*x*(k+3) + (k+1)/G(k+1) )); (continued fraction). - Sergei N. Gladkovskii, Jul 31 2013
EXAMPLE
MATHEMATICA
Table[2^n*((2*n + 3)/4 + (-1)^n/4), {n, 0, 30}] (* Arkadiusz Wesolowski, Dec 28 2011 *)
LinearRecurrence[{2, 4, -8}, {1, 2, 8}, 40] (* Harvey P. Dale, Nov 09 2017 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Gary W. Adamson, Oct 21 2007
STATUS
approved