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A240055
Number of partitions of n such that (number of distinct parts) = m(1) - m(2), where m = multiplicity.
0
1, 1, 0, 0, 0, 2, 1, 1, 3, 2, 4, 5, 7, 6, 14, 11, 17, 22, 30, 28, 45, 55, 61, 78, 103, 114, 147, 183, 202, 269, 316, 372, 446, 565, 631, 778, 935, 1096, 1283, 1586, 1791, 2166, 2558, 2991, 3478, 4182, 4821, 5616, 6660, 7716, 8933, 10532, 12155, 14058, 16482
OFFSET
0,6
EXAMPLE
a(10) counts these 4 partitions: 622, 4411, 43111, 421111.
MATHEMATICA
z = 58; d[p_] := d[p] = Length[DeleteDuplicates[p]]; Table[Count[IntegerPartitions[n], p_ /; d[p] == Count[p, 1] - Count[p, 2]], {n, 0, z}]
CROSSREFS
Cf. A240056.
Sequence in context: A241472 A071872 A141038 * A156309 A205115 A334369
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Mar 31 2014
STATUS
approved