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 A325243 Number of integer partitions of n with exactly two distinct multiplicities. 2
 0, 0, 0, 0, 1, 3, 3, 9, 12, 19, 26, 39, 47, 70, 89, 115, 148, 189, 235, 294, 362, 450, 558, 669, 817, 980, 1197, 1421, 1709, 2012, 2429, 2836, 3380, 3961, 4699, 5433, 6457, 7433, 8770, 10109, 11818, 13547, 15912, 18109, 21105, 24121, 27959, 31736, 36840, 41670 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,6 COMMENTS For example, (32211) has two distinct multiplicities (1 and 2) so is counted under a(9). The Heinz numbers of these partitions are given by A323055. LINKS EXAMPLE The a(4) = 1 through a(9) = 19 partitions:   (211)  (221)   (411)    (322)     (332)      (441)          (311)   (3111)   (331)     (422)      (522)          (2111)  (21111)  (511)     (611)      (711)                           (2221)    (3221)     (3222)                           (3211)    (4211)     (3321)                           (4111)    (5111)     (4221)                           (22111)   (22211)    (4311)                           (31111)   (32111)    (5211)                           (211111)  (41111)    (6111)                                     (221111)   (22221)                                     (311111)   (32211)                                     (2111111)  (33111)                                                (42111)                                                (51111)                                                (321111)                                                (411111)                                                (2211111)                                                (3111111)                                                (21111111) MATHEMATICA Table[Length[Select[IntegerPartitions[n], Length[Union[Length/@Split[#]]]==2&]], {n, 0, 30}] CROSSREFS Column k = 2 of A325242. Dominated by A325267. Cf. A008284, A062770, A071625, A098859, A116608, A244515, A323055, A325244. Sequence in context: A117153 A045810 A166720 * A319271 A066314 A083336 Adjacent sequences:  A325240 A325241 A325242 * A325244 A325245 A325246 KEYWORD nonn AUTHOR Gus Wiseman, Apr 15 2019 STATUS approved

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Last modified July 18 21:25 EDT 2019. Contains 325144 sequences. (Running on oeis4.)