This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A241550 #4 May 06 2014 15:03:30
%S A241550 0,1,1,2,3,5,7,10,14,21,28,39,51,70,92,122,158,206,265,343,432,554,
%T A241550 695,879,1098,1373,1703,2115,2607,3218,3937,4831,5882,7175,8699,10541,
%U A241550 12733,15358,18464,22184,26548,31774,37891,45166,53681,63743,75529,89381
%N A241550 Number of partitions p of n such that (number of numbers of the form 5k + 1 in p) is a part of p.
%C A241550 Each number in p is counted once, regardless of its multiplicity.
%e A241550 a(6) counts these 7 partitions: 51, 411, 321, 3111, 2211, 21111, 111111.
%t A241550 z = 30; f[n_] := f[n] = IntegerPartitions[n]; s[k_, p_] := Count[Mod[DeleteDuplicates[p], 5], k]
%t A241550 Table[Count[f[n], p_ /; MemberQ[p, s[0, p]]], {n, 0, z}] (* A241549 *)
%t A241550 Table[Count[f[n], p_ /; MemberQ[p, s[1, p]]], {n, 0, z}] (* A241550 *)
%t A241550 Table[Count[f[n], p_ /; MemberQ[p, s[2, p]]], {n, 0, z}] (* A241551 *)
%t A241550 Table[Count[f[n], p_ /; MemberQ[p, s[3, p]]], {n, 0, z}] (* A241552 *)
%t A241550 Table[Count[f[n], p_ /; MemberQ[p, s[4, p]]], {n, 0, z}] (* A241553 *)
%Y A241550 Cf. A241549, A241551, A241552, A241553.
%K A241550 nonn,easy
%O A241550 0,4
%A A241550 _Clark Kimberling_, Apr 26 2014