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.
%I A316891 #8 Jul 18 2018 19:20:37 %S A316891 1,0,0,0,1,0,1,0,2,1,5,2,7,4,7,6,13,7,18,12,20,17,32,20,39,31,47,45, %T A316891 74,56,96,83,109,105,151,130,199,183,234,232,319,286,404,386,473,488, %U A316891 638,599,782,767,931,960,1197,1165,1465,1477,1747,1814,2212,2196 %N A316891 Number of aperiodic integer partitions of n into relatively prime parts whose reciprocal sum is an integer. %C A316891 The reciprocal sum of (y_1, ..., y_k) is 1/y_1 + ... + 1/y_k. %C A316891 A partition is aperiodic if its multiplicities are relatively prime. %H A316891 Gus Wiseman, <a href="/A051908/a051908.txt">Sequences counting and ranking integer partitions by their reciprocal sums</a> %e A316891 The a(17) = 13 partitions: %e A316891 (6443), %e A316891 (44441), %e A316891 (3332222), (6322211), %e A316891 (44222111), %e A316891 (222222221), (333221111), (632111111), %e A316891 (4421111111), %e A316891 (22222211111), (33311111111), %e A316891 (2222111111111), %e A316891 (221111111111111). %t A316891 Table[Length[Select[IntegerPartitions[n],And[GCD@@#==1,GCD@@Length/@Split[#]==1,IntegerQ[Sum[1/m,{m,#}]]]&]],{n,50}] %Y A316891 Cf. A000837, A002966, A051908, A058360, A100953, A316854, A316856, A316888-A316904. %K A316891 nonn %O A316891 1,9 %A A316891 _Gus Wiseman_, Jul 16 2018 %E A316891 a(51)-a(60) from _Alois P. Heinz_, Jul 18 2018