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A134097
a(n) = 2^[n(n+1) - A000120(n)] * [x^n] 1/(1-x)^(1/2^n) for n>=0, where A000120(n) = number of 1's in binary expansion of n.
2
1, 1, 5, 51, 9163, 1789359, 2966784613, 10246481110899, 1164644624885859315, 67519816893223600328475, 31778915061906077887063371935, 30252957250679839624103772879830589
OFFSET
0,3
COMMENTS
[x^n] 1/(1-x)^(1/2^n) denotes the coefficient of x^n in the (2^n)-root of 1/(1-x).
PROG
(PARI) {a(n)=polcoeff(1/(1-x+x*O(x^n))^(1/2^n), n)*2^(n*(n+1)-subst(Pol(binary(n)), x, 1))}
CROSSREFS
Cf. A000120; A134098 (variant); A134096.
Sequence in context: A022516 A003515 A022501 * A299025 A247702 A247713
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Oct 26 2007
STATUS
approved