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 A090868 Number of partitions of n such that the set of odd parts has only one element. 1
 1, 1, 3, 2, 6, 5, 11, 8, 20, 15, 32, 24, 51, 39, 80, 58, 119, 90, 175, 130, 255, 190, 361, 268, 508, 379, 706, 522, 967, 722, 1313, 974, 1771, 1317, 2363, 1754, 3131, 2330, 4123, 3058, 5388, 4010, 7001, 5200, 9053, 6731, 11631, 8642, 14878, 11068, 18944, 14076 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Vaclav Kotesovec, Table of n, a(n) for n = 1..14572 (terms 1..5000 from Alois P. Heinz) FORMULA G.f.: Sum_{m>0} x^(2*m-1)/(1-x^(2*m-1))/Product_{m>0} (1-x^(2*m)). MAPLE b:= proc(n, i, t) option remember; `if`(n=0, `if`(t, 1, 0),       `if`(i<1, 0, add(b(n-i*j, i-1, t or j>0 and i::odd),        j=0..`if`(t and i::odd, 0, n/i))))     end: a:= n-> b(n\$2, false): seq(a(n), n=1..60);  # Alois P. Heinz, Jun 30 2016 MATHEMATICA first Needs["DiscreteMath`Combinatorica`"], then f[n_] := Count[ Plus @@@ Mod[ Union /@ Partitions[n], 2], 1]; Table[ f[n], {n, 1, 51}] (* Robert G. Wilson v, Feb 16 2004 *) CROSSREFS Cf. A066897. Sequence in context: A278504 A085179 A113782 * A125675 A301501 A072787 Adjacent sequences:  A090865 A090866 A090867 * A090869 A090870 A090871 KEYWORD easy,nonn AUTHOR Vladeta Jovovic, Feb 12 2004 EXTENSIONS More terms from Robert G. Wilson v, Feb 16 2004 STATUS approved

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Last modified May 26 07:53 EDT 2020. Contains 334620 sequences. (Running on oeis4.)