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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.

A357858 Number of integer partitions that can be obtained by iteratively adding and multiplying together parts of the integer partition with Heinz number n.

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%I A357858 #7 Oct 17 2022 12:32:10
%S A357858 1,1,1,3,1,3,1,6,2,3,1,7,1,3,3,11,1,7,1,8,3,3,1,14,3,3,4,8,1,11,1,19,
%T A357858 3,3,3,18,1,3,3,18,1,12,1,8,8,3,1,27,3,10,3,8,1,16,3,19,3,3,1,25,1,3,
%U A357858 8,33,3,12,1,8,3,12,1,35,1,3,11,8,3,12,1,34,9
%N A357858 Number of integer partitions that can be obtained by iteratively adding and multiplying together parts of the integer partition with Heinz number n.
%C A357858 The Heinz number of a partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k). This gives a bijective correspondence between positive integers and integer partitions.
%e A357858 The a(n) partitions for n = 1, 4, 8, 9, 12, 16, 20, 24:
%e A357858   ()  (1)   (1)    (4)   (2)    (1)     (3)    (2)
%e A357858       (2)   (2)    (22)  (3)    (2)     (4)    (3)
%e A357858       (11)  (3)          (4)    (3)     (5)    (4)
%e A357858             (11)         (21)   (4)     (6)    (5)
%e A357858             (21)         (22)   (11)    (31)   (6)
%e A357858             (111)        (31)   (21)    (32)   (21)
%e A357858                          (211)  (22)    (41)   (22)
%e A357858                                 (31)    (311)  (31)
%e A357858                                 (111)          (32)
%e A357858                                 (211)          (41)
%e A357858                                 (1111)         (211)
%e A357858                                                (221)
%e A357858                                                (311)
%e A357858                                                (2111)
%t A357858 primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
%t A357858 ReplaceListRepeated[forms_,rerules_]:=Union[Flatten[FixedPointList[Function[pre,Union[Flatten[ReplaceList[#,rerules]&/@pre,1]]],forms],1]];
%t A357858 Table[Length[ReplaceListRepeated[{primeMS[n]},{{foe___,x_,mie___,y_,afe___}:>Sort[Append[{foe,mie,afe},x+y]],{foe___,x_,mie___,y_,afe___}:>Sort[Append[{foe,mie,afe},x*y]]}]],{n,100}]
%Y A357858 The single-part partitions are counted by A319841, with an inverse A319913.
%Y A357858 The minimum is A319855, maximum A319856.
%Y A357858 A000041 counts integer partitions.
%Y A357858 A001222 counts prime indices, distinct A001221.
%Y A357858 A056239 adds up prime indices.
%Y A357858 A066739 counts representations as a sum of products.
%Y A357858 Cf. A000792, A001055, A001970, A005520, A048249, A063834, A066815, A318948, A319850, A319909, A319910.
%K A357858 nonn
%O A357858 1,4
%A A357858 _Gus Wiseman_, Oct 17 2022