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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.

A334126 a(n) is the smallest positive integer not already in the sequence such that Sum_{i=k..n} a(i) is not a perfect power for 0 < k < n; start with a(1)=1.

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%I A334126 #17 Jun 22 2022 09:25:17
%S A334126 1,2,3,7,5,6,17,12,8,10,4,16,13,11,15,18,19,9,14,23,20,30,22,21,26,36,
%T A334126 29,24,27,32,25,33,34,35,28,46,31,37,47,38,39,49,41,48,40,42,50,43,44,
%U A334126 51,45,52,53,56,54,58,59,55,62,65,68,67,57,63,64,70,61,69
%N A334126 a(n) is the smallest positive integer not already in the sequence such that Sum_{i=k..n} a(i) is not a perfect power for 0 < k < n; start with a(1)=1.
%C A334126 I conjecture that every number eventually appears.
%C A334126 Let b(1) = 1; b(2*m) is the least positive integer not occurring earlier in b(i), i=1..2*m-2; b(2*m-1) is the least positive integer not already in {b(n)} such that Sum_{i=j..2*m-1} b(i) and Sum_{i=k..2*m} b(i) are not perfect powers for 0 < j < 2*m-1 and 0 < k < 2*m. Then {b(n)} is a permutation of the positive integers such that Sum_{i=k..m} b(i) is not a perfect power for any 0 < k < m.
%o A334126 (PARI) lista(nn) = {my(k, s, v=vector(nn)); v[1]=1; for(n=2, nn, k=s=2; while(vecsearch(vecsort(v), k) || sum(i=1, n-1, ispower(s+=v[n-i])), s=k++); v[n]=k); v; }
%Y A334126 Cf. A001597, A127397.
%K A334126 nonn
%O A334126 1,2
%A A334126 _Jinyuan Wang_, May 10 2020