login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A240487
Number of partitions of n containing m(2) as a part, where m denotes multiplicity.
5
0, 0, 0, 1, 2, 2, 3, 5, 7, 11, 15, 20, 29, 39, 51, 70, 92, 119, 157, 203, 259, 334, 424, 535, 678, 850, 1059, 1324, 1642, 2027, 2503, 3075, 3763, 4604, 5607, 6809, 8261, 9988, 12043, 14508, 17424, 20879, 24988, 29835, 35548, 42303, 50232, 59544, 70491, 83297
OFFSET
0,5
EXAMPLE
a(7) counts these 5 partitions: 421, 322, 3211, 22111, 211111.
MATHEMATICA
z = 60; f[n_] := f[n] = IntegerPartitions[n];
Table[Count[f[n], p_ /; MemberQ[p, Count[p, 1]]], {n, 0, z}] (* A240486 *)
Table[Count[f[n], p_ /; MemberQ[p, Count[p, 2]]], {n, 0, z}] (* A240487 *)
Table[Count[f[n], p_ /; MemberQ[p, Count[p, 3]]], {n, 0, z}] (* A240488 *)
Table[Count[f[n], p_ /; MemberQ[p, Count[p, 4]]], {n, 0, z}] (* A240489 *)
Table[Count[f[n], p_ /; MemberQ[p, Count[p, 5]]], {n, 0, z}] (* A240490 *)
CROSSREFS
Sequence in context: A322429 A039894 A133225 * A066889 A214040 A077419
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Apr 06 2014
STATUS
approved