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 A280996 #13 Nov 04 2023 14:00:22
%S A280996 2,3,5,7,11,17,19,23,31,53,59,67,83,97,103,127,131,227,241,277,311,
%T A280996 331,419,431,509,563,661,691,709,719,739,1433,1523,1543,1619,1787,
%U A280996 1879,2063,2221,2309,2437,2897,3001,3637,3671,3803,4091,4637,4943,5189,5381
%N A280996 Prime Matula-Goebel numbers of generalized Bethe trees.
%C A280996 Also prime numbers p whose index pi(p) is the Matula-Goebel number of a planted achiral tree.
%C A280996 An alternative definition: prime(n) is in the sequence iff n is a perfect power of a prime number already in the sequence.
%F A280996 a(1) = 2; a(n+1) = prime(A214577(n)).
%e A280996 a(n) = prime(Product_{i in y} a(i)) where y is the n-th partition in the following sequence, which spans all constant partitions: 1,2,11,3,4,111,22,5,1111,6,7,8,33,222,9,11111,44,...
%t A280996 nn=10000;
%t A280996 BTQ[n_]:=Or[n===1,MatchQ[PrimePi/@FactorInteger[n][[All,1]],{_?BTQ}]];
%t A280996 Prime/@Select[Range[PrimePi[nn]],BTQ]
%Y A280996 Cf. A003238, A214577, A280994, A276625, A277098, A007097.
%K A280996 nonn
%O A280996 1,1
%A A280996 _Gus Wiseman_, Jan 12 2017