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 A375702 #10 Aug 29 2024 12:15:53 %S A375702 2,3,6,8,1,4,3,12,14,16,18,20,3,2,15,24,26,19,8,17,12,32,34,18,17,38, %T A375702 40,42,27,16,46,48,50,52,54,56,58,60,38,23,64,66,68,70,34,37,74,76,78, %U A375702 80,46,35,84,86,88,22,67,70,9,11,94,96,98,100,102,39,64 %N A375702 Length of the n-th maximal run of adjacent (increasing by one at a time) non-perfect-powers. %C A375702 Non-perfect-powers A007916 are numbers with no proper integer roots. %F A375702 For n > 2 we have a(n) = A053289(n+1) - 1. %e A375702 The list of all non-perfect-powers, split into runs, begins: %e A375702 2 3 %e A375702 5 6 7 %e A375702 10 11 12 13 14 15 %e A375702 17 18 19 20 21 22 23 24 %e A375702 26 %e A375702 28 29 30 31 %e A375702 33 34 35 %e A375702 37 38 39 40 41 42 43 44 45 46 47 48 %e A375702 Row n has length a(n), first A375703, last A375704, sum A375705. %t A375702 radQ[n_]:=n>1&&GCD@@Last/@FactorInteger[n]==1; %t A375702 Length/@Split[Select[Range[100],radQ],#1+1==#2&]//Most %Y A375702 For nonsquarefree numbers we have A053797, anti-runs A373409. %Y A375702 For squarefree numbers we have A120992, anti-runs A373127. %Y A375702 For nonprime numbers we have A176246, anti-runs A373403. %Y A375702 For prime-powers we have A373675, anti-runs A373576. %Y A375702 For non-prime-powers we have A373678, anti-runs A373679. %Y A375702 The anti-run version is A375736, sum A375737. %Y A375702 For runs of non-perfect-powers (A007916): %Y A375702 - length: A375702 (this). %Y A375702 - first: A375703 %Y A375702 - last: A375704 %Y A375702 - sum: A375705 %Y A375702 A001597 lists perfect-powers, differences A053289. %Y A375702 A007916 lists non-perfect-powers, differences A375706. %Y A375702 A046933 counts composite numbers between primes. %Y A375702 Cf. A007674, A045542, A061399, A216765, A251092, A375708, A375714. %K A375702 nonn %O A375702 1,1 %A A375702 _Gus Wiseman_, Aug 27 2024