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A240870
Number of partitions of n into distinct parts of which the number of odd parts is not a part.
3
0, 0, 1, 1, 2, 2, 3, 3, 5, 5, 7, 7, 11, 11, 15, 16, 22, 23, 31, 32, 42, 45, 58, 62, 79, 84, 106, 114, 140, 151, 187, 201, 244, 265, 319, 346, 413, 449, 533, 580, 683, 744, 873, 951, 1106, 1209, 1400, 1529, 1764, 1927, 2212, 2418, 2763, 3021, 3442, 3763, 4270
OFFSET
0,5
FORMULA
a(n) + A240574(n) = A000009(n) for n >= 1.
EXAMPLE
a(9) counts these 5 partitions: 9, 72, 63, 54, 432.
MATHEMATICA
z = 40; f[n_] := f[n] = Select[IntegerPartitions[n], Max[Length /@ Split@#] == 1 &];
t1 = Table[Count[f[n], p_ /; ! MemberQ[p, Count[Mod[p, 2], 0]]], {n, 0, z}] (* A240869 *)
t2 = Table[Count[f[n], p_ /; ! MemberQ[p, Count[Mod[p, 2], 1]]], {n, 0, z}] (* A240870 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Apr 14 2014
STATUS
approved