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A137206
First differences of A074323.
1
0, 2, -1, 4, -2, 8, -4, 16, -8, 32, -16, 64, -32, 128, -64, 256, -128, 512, -256, 1024, -512, 2048, -1024, 4096, -2048, 8192, -4096, 16384, -8192, 32768, -16384, 65536, -32768, 131072, -65536, 262144, -131072, 524288, -262144, 1048576, -524288
OFFSET
0,2
FORMULA
From R. J. Mathar, Apr 22 2009: (Start)
G.f.: x*(2-x)/(1-2*x^2).
a(n) = (-1)^(n+1)*A135530(n-1). (End)
a(n) = 2*a(n-2). - Matthew House, Jan 15 2017
CROSSREFS
KEYWORD
sign
AUTHOR
Paul Curtz, Mar 05 2008
EXTENSIONS
More terms from R. J. Mathar, Apr 22 2009
STATUS
approved