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A241550
Number of partitions p of n such that (number of numbers of the form 5k + 1 in p) is a part of p.
5
0, 1, 1, 2, 3, 5, 7, 10, 14, 21, 28, 39, 51, 70, 92, 122, 158, 206, 265, 343, 432, 554, 695, 879, 1098, 1373, 1703, 2115, 2607, 3218, 3937, 4831, 5882, 7175, 8699, 10541, 12733, 15358, 18464, 22184, 26548, 31774, 37891, 45166, 53681, 63743, 75529, 89381
OFFSET
0,4
COMMENTS
Each number in p is counted once, regardless of its multiplicity.
EXAMPLE
a(6) counts these 7 partitions: 51, 411, 321, 3111, 2211, 21111, 111111.
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 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Apr 26 2014
STATUS
approved