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 A291441 #13 Jun 21 2020 01:57:23
%S A291441 1,4,8,16,32,49,64,128,256,343,361,512,1024,2048,2401,2809,4096,6859,
%T A291441 8192,12031,16384,16807,17161,32768,51529,65536,96721,117649,130321,
%U A291441 131072,148877,262144,516961,524288,637643,718099,757907,823543,1048576,2097152,2248091
%N A291441 Matula-Goebel numbers of orderless same-trees with all leaves equal to 1.
%C A291441 See A289078 for the definition of orderless same-tree.
%e A291441 a(20)=12031 corresponds to the following same-tree: {{1,1,1,1},{{1,1},{1,1}}}.
%t A291441 nn=200000;
%t A291441 primeMS[n_]:=If[n===1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
%t A291441 leafcount[n_]:=If[n===1,1,With[{m=primeMS[n]},If[Length[m]===1,leafcount[First[m]],Total[leafcount/@m]]]];
%t A291441 sameQ[n_]:=Or[n===1,With[{m=primeMS[n]},And[Length[m]>1,SameQ@@leafcount/@m,And@@sameQ/@m]]];
%t A291441 Select[Range[nn],sameQ]
%Y A291441 Cf. A007097, A109129, A214577, A280994, A289078, A289079, A291442, A291443.
%K A291441 nonn
%O A291441 1,2
%A A291441 _Gus Wiseman_, Aug 23 2017
%E A291441 More terms from _Jinyuan Wang_, Jun 21 2020