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 A324701 #8 Mar 11 2019 20:48:41
%S A324701 1,3,5,6,9,11,12,14,17,21,23,24,26,27,32,33,38,41,44,45,47,51,53,56,
%T A324701 60,63,65,66,74,75,81,84,87,89,90,93,101,102,104,105,111,116,119,122,
%U A324701 125,126,129,131,132,138,144,147,149,156,161,164,167,170,173,177
%N A324701 Lexicographically earliest sequence containing 1 and all positive integers n such that the prime indices of n - 1 already belong to the sequence.
%C A324701 A self-describing sequence, similar to A304360.
%C A324701 A prime index of n is a number m such that prime(m) divides n. The multiset of prime indices of n is row n of A112798.
%F A324701 a(n) = A324700(n) + 1.
%t A324701 aQ[n_]:=Switch[n,0,False,1,True,_,And@@Cases[FactorInteger[n-1],{p_,k_}:>aQ[PrimePi[p]]]];
%t A324701 Select[Range[0,100],aQ]
%Y A324701 Prime indices of A324700.
%Y A324701 Cf. A000002, A000720, A001222, A001462, A007097, A055396, A061395, A079000, A079254, A109298, A112798, A276625, A277098, A304360.
%Y A324701 Cf. A324694, A324695, A324696, A324697, A324698, A324699, A324702, A324703, A324704, A324705.
%K A324701 nonn
%O A324701 1,2
%A A324701 _Gus Wiseman_, Mar 10 2019