cp's OEIS Frontend

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.

A316895 Number of aperiodic integer partitions of n whose reciprocal sum is an integer.

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%I A316895 #8 Jul 17 2018 17:39:01
%S A316895 1,0,0,0,1,0,1,0,2,2,5,2,7,5,7,6,13,8,18,13,20,19,32,21,39,35,49,48,
%T A316895 74,60,96,86,110,111,151,135,199,192,235,239,319,299,404,394,477,506,
%U A316895 638,609,782,788,934,978,1197,1193,1466,1501,1752,1851,2212,2227
%N A316895 Number of aperiodic integer partitions of n whose reciprocal sum is an integer.
%C A316895 The reciprocal sum of (y_1, ..., y_k) is 1/y_1 + ... + 1/y_k.
%C A316895 A partition is aperiodic if its multiplicities are relatively prime.
%H A316895 Gus Wiseman, <a href="/A051908/a051908.txt">Sequences counting and ranking integer partitions by their reciprocal sums</a>
%e A316895 The a(11) = 5 partitions are (632), (4421), (33311), (2222111), (221111111).
%t A316895 Table[Length[Select[IntegerPartitions[n],And[GCD@@Length/@Split[#]==1,IntegerQ[Sum[1/m,{m,#}]]]&]],{n,30}]
%Y A316895 Cf. A000837, A002966, A051908, A058360, A100953, A316854, A316888-A316904.
%K A316895 nonn
%O A316895 1,9
%A A316895 _Gus Wiseman_, Jul 16 2018
%E A316895 a(51)-a(60) from _Alois P. Heinz_, Jul 17 2018