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A055895
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Inverse Moebius transform of powers of 2.
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3
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1, 2, 6, 10, 22, 34, 78, 130, 278, 522, 1062, 2050, 4190, 8194, 16518, 32810, 65814, 131074, 262734, 524290, 1049654, 2097290, 4196358, 8388610, 16781662, 33554466, 67117062, 134218250, 268451990, 536870914, 1073775726
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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LINKS
| N. J. A. Sloane, Transforms
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FORMULA
| G.f.: sum(k>=1, 1/(1-2*x^k)) - Benoit Cloitre (benoit7848c(AT)orange.fr), Apr 21 2003
G.f.: sum(k>=1, 2^k*x^k/(1-x^k)). - Benoit Cloitre (benoit7848c(AT)orange.fr), Apr 21 2003
a(n) = sum( 2^d, d divides n) - Olivier Gérard, Jan 01, 2012
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MATHEMATICA
| Table[Plus @@ Map[Function[d, 2^d], Divisors[n]], {n, 0, 30}] (* Olivier Gérard, Jan 01, 2012 *)
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PROG
| (PARI) a(n)=if(n<1, 0, polcoeff(sum(k=1, n, 1/(1-2*x^k), x*O(x^n)), n))
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CROSSREFS
| Cf. A055894.
Sequence in context: A034168 A055745 A167512 * A125527 A200572 A049750
Adjacent sequences: A055892 A055893 A055894 * A055896 A055897 A055898
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KEYWORD
| nonn
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AUTHOR
| Christian G. Bower (bowerc(AT)usa.net), Jun 09 2000
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