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 A325759 #6 May 19 2019 20:33:12
%S A325759 0,1,1,2,1,2,1,2,1,3,1,2,1,3,3,2,1,2,1,3,3,3,1,3,2,3,2,3,1,3,1,2,3,3,
%T A325759 4,2,1,3,3,3,1,4,1,3,3,3,1,3,2,3,3,3,1,3,4,4,3,3,1,3,1,3,3,2,4,4,1,3,
%U A325759 3,3,1,3,1,3,3,3,4,4,1,4,2,3,1,3,4,3,3
%N A325759 Number of distinct frequencies in the frequency span of n.
%C A325759 We define the frequency span of an integer partition to be the partition itself if it has no or only one block, and otherwise it is the multiset union of the partition and the frequency span of its multiplicities. For example, the frequency span of (3,2,2,1) is {1,2,2,3} U {1,1,2} U {1,2} U {1,1} U {2} = {1,1,1,1,1,1,2,2,2,2,2,3}. The frequency span of a positive integer n is the frequency span of its prime indices (row n of A296150).
%t A325759 primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
%t A325759 freqspan[ptn_]:=If[Length[ptn]<=1,ptn,Sort[Join[ptn,freqspan[Sort[Length/@Split[ptn]]]]]];
%t A325759 Table[Length[Union[freqspan[primeMS[n]]]],{n,100}]
%Y A325759 Row lengths of A325758.
%Y A325759 Number of distinct entries in row n of A325757.
%Y A325759 Cf. A001221, A001222, A056239, A071625, A112798, A181819, A182857, A323014, A325249, A325277, A325760.
%K A325759 nonn
%O A325759 1,4
%A A325759 _Gus Wiseman_, May 19 2019