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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.

A331387 Number of integer partitions whose sum of primes of parts equals their sum of parts plus n.

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%I A331387 #15 Apr 17 2021 14:13:45
%S A331387 1,2,4,7,11,16,24,34,47,64,86,113,148,191,245,310,390,486,602,740,907,
%T A331387 1104,1338,1613,1937,2315,2758,3272,3871,4562,5362,6283,7344,8558,
%U A331387 9952,11542,13356,15419,17766,20425,23440,26846,30696,35032,39917,45406
%N A331387 Number of integer partitions whose sum of primes of parts equals their sum of parts plus n.
%C A331387 Primes of parts means the prime counting function applied to the part sizes. Equivalently, a(n) is the number of integer partitions with part sizes in A014689(n) interpreted as a multiset. - _Andrew Howroyd_, Apr 17 2021
%H A331387 Andrew Howroyd, <a href="/A331387/b331387.txt">Table of n, a(n) for n = 0..1000</a>
%F A331387 G.f.: 1/Product_{k>=1} 1 - x^(prime(k)-k). - _Andrew Howroyd_, Apr 16 2021
%e A331387 The a(0) = 1 through a(5) = 16 partitions:
%e A331387   ()  (1)  (3)   (4)    (33)    (43)
%e A331387       (2)  (11)  (31)   (41)    (331)
%e A331387            (21)  (32)   (42)    (332)
%e A331387            (22)  (111)  (311)   (411)
%e A331387                  (211)  (321)   (421)
%e A331387                  (221)  (322)   (422)
%e A331387                  (222)  (1111)  (3111)
%e A331387                         (2111)  (3211)
%e A331387                         (2211)  (3221)
%e A331387                         (2221)  (3222)
%e A331387                         (2222)  (11111)
%e A331387                                 (21111)
%e A331387                                 (22111)
%e A331387                                 (22211)
%e A331387                                 (22221)
%e A331387                                 (22222)
%e A331387 For example, the partition (3,2,2,1) is counted under n = 5 because it has sum of primes 5+3+3+2 = 13 and its sum of parts plus n is also 3+2+2+1+5 = 13.
%t A331387 Table[Sum[Length[Select[IntegerPartitions[k],Total[Prime/@#]==k+n&]],{k,0,2*n}],{n,0,10}]
%o A331387 (PARI) seq(n)={my(m=1); while(prime(m)-m<=n, m++); Vec(1/prod(k=1, m, 1 - x^(prime(k)-k) + O(x*x^n)))} \\ _Andrew Howroyd_, Apr 16 2021
%Y A331387 Column sums of A331385.
%Y A331387 Partitions into primes are A000607.
%Y A331387 Partitions whose sum of primes is divisible by their sum are A331379.
%Y A331387 Partitions whose product divides their sum of primes are A331381.
%Y A331387 Partitions whose product equals their sum of primes are A331383.
%Y A331387 Cf. A000040, A001414, A014689, A056239, A330950, A330953, A330954, A331378, A331415, A331416, A331418.
%K A331387 nonn
%O A331387 0,2
%A A331387 _Gus Wiseman_, Jan 17 2020
%E A331387 Terms a(31) and beyond from _Andrew Howroyd_, Apr 16 2021