OFFSET
1,2
LINKS
FORMULA
Even-indexed terms, a(n) = 2^n; odd-indexed terms, a(n) = 2^(n-1) + 2^(n-2).
G.f.: -x*(4*x+1+2*x^2)/(2*x-1)/(2*x+1). - R. J. Mathar, Nov 14 2007
EXAMPLE
a(4) = 16 = sum or row 4 terms of triangle A133571: (5 + 5 + 5 + 1).
a(4) = 16 = 2^4.
a(7) = 96 = 2^6 + 2^5 = 64 + 32.
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Gary W. Adamson, Sep 16 2007
STATUS
approved