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A264687
a(n) = 2^n - A006951(n).
3
0, 1, 1, 2, 2, 5, 4, 11, 10, 22, 22, 50, 43, 104, 100, 209, 206, 446, 418, 914, 886, 1838, 1825, 3800, 3664, 7696, 7591, 15470, 15370, 31466, 30910, 63398, 62866, 127154, 126742, 256559, 254156, 515168, 513004, 1032104, 1029997, 2073626, 2063866, 4156118
OFFSET
0,4
LINKS
FORMULA
a(n) ~ (1+sqrt(2) + (-1)^n*(1-sqrt(2))) * 2^(n/2 - 1).
MATHEMATICA
nmax = 60; 2^Range[0, nmax] - CoefficientList[Series[Product[(1 - x^k)/(1 - 2*x^k), {k, 1, nmax}], {x, 0, nmax}], x]
CROSSREFS
Sequence in context: A338528 A238624 A124506 * A112471 A144366 A054156
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, Nov 21 2015
STATUS
approved