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A240573
Number of partitions of n such that the number of even parts is a part.
15
0, 0, 0, 1, 2, 3, 5, 7, 10, 15, 21, 28, 38, 51, 67, 89, 116, 149, 192, 245, 310, 393, 494, 617, 770, 956, 1181, 1457, 1790, 2190, 2675, 3257, 3952, 4788, 5784, 6968, 8380, 10053, 12032, 14378, 17144, 20400, 24236, 28740, 34018, 40208, 47443, 55887, 65744
OFFSET
0,5
EXAMPLE
a(10) counts these 21 partitions: 82, 811, 721, 631, 6211, 61111, 541, 5221, 52111, 4321, 43111, 4222, 421111, 4111111, 3322, 33211, 32221, 322111, 3211111, 22111111, 211111111.
MATHEMATICA
z = 62; f[n_] := f[n] = IntegerPartitions[n];
Table[Count[f[n], p_ /; MemberQ[p, Count[Mod[p, 2], 0]]], {n, 0, z}]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Apr 10 2014
STATUS
approved