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 A325243 #4 Apr 16 2019 15:26:42 %S A325243 0,0,0,0,1,3,3,9,12,19,26,39,47,70,89,115,148,189,235,294,362,450,558, %T A325243 669,817,980,1197,1421,1709,2012,2429,2836,3380,3961,4699,5433,6457, %U A325243 7433,8770,10109,11818,13547,15912,18109,21105,24121,27959,31736,36840,41670 %N A325243 Number of integer partitions of n with exactly two distinct multiplicities. %C A325243 For example, (32211) has two distinct multiplicities (1 and 2) so is counted under a(9). %C A325243 The Heinz numbers of these partitions are given by A323055. %e A325243 The a(4) = 1 through a(9) = 19 partitions: %e A325243 (211) (221) (411) (322) (332) (441) %e A325243 (311) (3111) (331) (422) (522) %e A325243 (2111) (21111) (511) (611) (711) %e A325243 (2221) (3221) (3222) %e A325243 (3211) (4211) (3321) %e A325243 (4111) (5111) (4221) %e A325243 (22111) (22211) (4311) %e A325243 (31111) (32111) (5211) %e A325243 (211111) (41111) (6111) %e A325243 (221111) (22221) %e A325243 (311111) (32211) %e A325243 (2111111) (33111) %e A325243 (42111) %e A325243 (51111) %e A325243 (321111) %e A325243 (411111) %e A325243 (2211111) %e A325243 (3111111) %e A325243 (21111111) %t A325243 Table[Length[Select[IntegerPartitions[n],Length[Union[Length/@Split[#]]]==2&]],{n,0,30}] %Y A325243 Column k = 2 of A325242. Dominated by A325267. %Y A325243 Cf. A008284, A062770, A071625, A098859, A116608, A244515, A323055, A325244. %K A325243 nonn %O A325243 0,6 %A A325243 _Gus Wiseman_, Apr 15 2019