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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.

A325243 Number of integer partitions of n with exactly two distinct multiplicities.

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%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