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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.

A316900 Heinz numbers of integer partitions into relatively prime parts whose reciprocal sum is an integer.

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%I A316900 #6 Jul 17 2018 08:09:12
%S A316900 2,4,8,16,18,32,36,64,72,128,144,162,195,250,256,288,294,324,390,500,
%T A316900 512,576,588,648,780,1000,1024,1125,1152,1176,1296,1458,1560,1755,
%U A316900 2000,2048,2250,2304,2352,2592,2646,2916,3120,3185,3510,4000,4096,4500,4608
%N A316900 Heinz numbers of integer partitions into relatively prime parts whose reciprocal sum is an integer.
%C A316900 The reciprocal sum of (y_1, ..., y_k) is 1/y_1 + ... + 1/y_k.
%C A316900 The Heinz number of an integer partition (y_1, ..., y_k) is prime(y_1) * ... * prime(y_k).
%H A316900 Gus Wiseman, <a href="/A051908/a051908.txt">Sequences counting and ranking integer partitions by their reciprocal sums</a>
%e A316900 The sequence of partitions whose Heinz numbers belong to this sequence begins: (1), (11), (111), (1111), (221), (11111), (2211), (111111), (22111), (1111111), (221111), (22221), (632), (3331), (11111111).
%t A316900 Select[Range[2,1000],And[GCD@@PrimePi/@FactorInteger[#][[All,1]]==1,IntegerQ[Sum[m[[2]]/PrimePi[m[[1]]],{m,FactorInteger[#]}]]]&]
%Y A316900 Cf. A000837, A002966, A051908, A058360, A100953, A289509, A296150, A316854, A316855, A316856, A316857, A316888-A316904.
%K A316900 nonn
%O A316900 1,1
%A A316900 _Gus Wiseman_, Jul 16 2018