OFFSET
0,3
FORMULA
-a(2n+3) = a(2n) = A002487(n+2), n >= 0. - Ralf Stephan, Aug 17 2003
G.f.: -1/x^2 + ((1 - x)/x^2)*Product_{k>=0} (1 + x^(2^k) + x^(2^(k+1))). - Ilya Gutkovskiy, Feb 28 2017
CROSSREFS
KEYWORD
sign
AUTHOR
N. J. A. Sloane, May 24 2002
STATUS
approved