A161064 Number of partitions of n into powers of two minus one where every part appears at least 2 times.

0, 1, 1, 1, 1, 2, 1, 2, 3, 2, 3, 4, 3, 5, 5, 5, 6, 7, 6, 8, 9, 8, 11, 11, 11, 13, 14, 14, 16, 19, 17, 21, 22, 22, 25, 27, 27, 30, 33, 32, 36, 39, 38, 44, 46, 46, 51, 54, 54, 59, 64, 62, 70, 73, 73, 80, 84, 85, 92, 98, 97, 107, 111, 112, 122, 127, 128, 139, 144, 146, 157, 164, 165, 179

Offset

1,6

Links

R. H. Hardin, Table of n, a(n) for n = 1..1000

Formula

G.f.: Product_{j>=1} (1 + x^(2*(2^j-1))/(1-x^(2^j-1))). - Emeric Deutsch, Jun 28 2009

Example

a(16)=5 because we have 7711, 33331111, 3331^7, 331^(10), and 1^(16). - Emeric Deutsch, Jun 28 2009

Maple

g := product(1+x^(2*(2^j-1))/(1-x^(2^j-1)), j = 1 .. 20): gser := series(g, x = 0, 80): seq(coeff(gser, x, n), n = 1 .. 74); # Emeric Deutsch, Jun 28 2009

Crossrefs

Sequence in context: A253174 A008611 A025798 * A070086 A211990 A162618

Adjacent sequences: A161061 A161062 A161063 * A161065 A161066 A161067

Keyword

nonn

Author

R. H. Hardin, Jun 02 2009

Status

approved