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 A357987 #6 Oct 24 2022 11:13:35 %S A357987 2,3,2,5,5,2,3,2,21,5,2,5,5,5,7,6,5,6,6,7,11,24,2,13,5,6,35,7,10,34,6, %T A357987 15,2,28,10,2,5,14,19,2,5,28,2,3,2,35,2,18,6,11,3,3,37,2,5,26,29,33, %U A357987 42,13,5,5,10,11,13,21,18,5,10,5,6,7,24,20,3,15 %N A357987 Lexicographically earliest sequence of positive integers such that no sum of consecutive terms is a square or higher power of an integer. %C A357987 This sequence is a variant of A357579 where we allow duplicates. %C A357987 This sequence is well defined as we have arbitrary large gaps in A001597. %H A357987 Rémy Sigrist, <a href="/A357987/a357987.txt">C program</a> %e A357987 For n = 1: %e A357987 - 2 is not a perfect power, %e A357987 - so a(1) = 2. %e A357987 For n = 2: %e A357987 - 2 + 2 is a perfect power, %e A357987 - neither 2 + 3 nor 3 are perfect powers, %e A357987 - so a(2) = 3. %e A357987 For n = 3: %e A357987 - none of 2 + 3 + 2, 3 + 2, 2 is a perfect power, %e A357987 - so a(3) = 2. %o A357987 (C) See Links section. %Y A357987 Cf. A001597, A007916, A357579. %K A357987 nonn %O A357987 1,1 %A A357987 _Rémy Sigrist_, Oct 23 2022