OFFSET
0,2
LINKS
FORMULA
a(0) = 1, a(2) = 5, a(n) = 2^(n+2) for n > 1.
G.f.: -(1 + 3*x + 6*x^2)/(-1 + 2*x). - R. J. Mathar, Nov 14 2007
E.g.f.: 4*exp(2*x) - 3*(1 + x). - Stefano Spezia, Feb 20 2023
EXAMPLE
a(3) = 32 = sum of row 3 terms of triangle A132478: (4 + 9 + 18 + 1).
a(3) = 32 = 2^5.
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Gary W. Adamson, Aug 23 2007
EXTENSIONS
More terms from Stefano Spezia, Feb 20 2023
STATUS
approved