A241551 Number of partitions p of n such that (number of numbers of the form 5k + 2 in p) is a part of p.
0, 0, 0, 1, 1, 2, 3, 5, 8, 13, 16, 25, 34, 49, 66, 90, 119, 161, 211, 279, 357, 465, 595, 764, 968, 1224, 1536, 1933, 2406, 2999, 3703, 4577, 5628, 6910, 8441, 10295, 12507, 15184, 18356, 22163, 26661, 32035, 38395, 45937, 54821, 65321, 77655, 92209, 109242
Offset: 0
Examples
a(6) counts these 3 partitions: 321, 2211, 21111.
Programs
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Mathematica
z = 30; f[n_] := f[n] = IntegerPartitions[n]; s[k_, p_] := Count[Mod[DeleteDuplicates[p], 5], k] Table[Count[f[n], p_ /; MemberQ[p, s[0, p]]], {n, 0, z}] (* A241549 *) Table[Count[f[n], p_ /; MemberQ[p, s[1, p]]], {n, 0, z}] (* A241550 *) Table[Count[f[n], p_ /; MemberQ[p, s[2, p]]], {n, 0, z}] (* A241551 *) Table[Count[f[n], p_ /; MemberQ[p, s[3, p]]], {n, 0, z}] (* A241552 *) Table[Count[f[n], p_ /; MemberQ[p, s[4, p]]], {n, 0, z}] (* A241553 *)
Comments