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A240863 revision #2

A240863
Number of partitions of n into distinct parts of which the number of odd parts is a part.
7
0, 1, 0, 1, 0, 1, 1, 2, 1, 3, 3, 5, 4, 7, 7, 11, 10, 15, 15, 22, 22, 31, 31, 42, 43, 58, 59, 78, 82, 105, 109, 139, 146, 183, 193, 239, 255, 311, 331, 402, 430, 516, 553, 659, 710, 839, 904, 1061, 1146, 1337, 1446, 1679, 1819, 2099, 2276, 2615, 2838, 3246
OFFSET
0,8
FORMULA
a(n) + A240870(n) = A000009(n) for n >= 0.
EXAMPLE
a(10) counts these 3 partitions: 721, 532, 4321.
MATHEMATICA
z = 70; 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}] (* A240862 *)
t2 = Table[Count[f[n], p_ /; MemberQ[p, Count[Mod[p, 2], 1]]], {n, 0, z}] (* A240863, *)
t3 = Table[Count[f[n], p_ /; MemberQ[p, Count[Mod[p, 2], 0]] && MemberQ[p, Count[Mod[p, 2], 1]]], {n, 0, z}] (* A240864 *)
t4 = Table[Count[f[n], p_ /; MemberQ[p, Count[Mod[p, 2], 0]] || MemberQ[p, Count[Mod[p, 2], 1]]], {n, 0, z}] (* A240865 *)
t5 = Table[Count[f[n], p_ /; MemberQ[p, Count[Mod[p, 2], 0]] && ! MemberQ[p, Count[Mod[p, 2], 1]]], {n, 0, z}] (* A240866 *)
t6 = Table[Count[f[n], p_ /; ! MemberQ[p, Count[Mod[p, 2], 0]] && MemberQ[p, Count[Mod[p, 2], 1]]], {n, 0, z}] (* A240867 *)
t7 = Table[Count[f[n], p_ /; ! MemberQ[p, Count[Mod[p, 2], 0]] && ! MemberQ[p, Count[Mod[p, 2], 1]]], {n, 0, z}] (* A240868 *)
CROSSREFS
Cf. A240862, A240864, A240865, A240866, A240867, A204868; for analogous sequences for unrestricted partitions, see A240573-A240579.
Sequence in context: A178133 A343379 A026927 * A288005 A237832 A074500
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Apr 14 2014
STATUS
editing