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 A375713 #8 Sep 08 2024 19:26:42 %S A375713 5,8,9,15,16,17,19,20,23,24,27,28,30,31,32,33,36,38,40,41,44,45,46,47, %T A375713 51,52,53,54,56,57,58,59,60,61,63,64,67,68,71,72,74,75,76,77,78,79,81, %U A375713 82,85,87,88,89,90,93,94,95,96,97,98,99,100,103,104,105,106 %N A375713 Indices of consecutive non-prime-powers (A361102) differing by 1. Numbers k such that the k-th and (k+1)-th non-prime-powers differ by just one. %F A375713 A361102(k+1) - A361102(k) = 1. %e A375713 The initial non-prime-powers are 1, 6, 10, 12, 14, 15, 18, 20, 21, which first increase by one after the fifth and eighth terms. %t A375713 Join@@Position[Differences[Select[Range[100],!PrimePowerQ[#]&]],1] %Y A375713 The inclusive version is a(n) - 1. %Y A375713 For prime-powers inclusive (A000961) we have A375734, differences A373671. %Y A375713 For nonprime numbers (A002808) we have A375926, differences A373403. %Y A375713 For prime-powers exclusive (A246655) we have A375734(n+1) + 1. %Y A375713 First differences are A373672. %Y A375713 Positions of 1's in A375708. %Y A375713 For non-perfect-powers we have A375740. %Y A375713 Prime-powers inclusive: %Y A375713 - terms: A000961 %Y A375713 - differences: A057820 %Y A375713 - runs: A373675, A373673, A373674, A174965 %Y A375713 - antiruns: A373576, A120430, A006549, A373671 %Y A375713 Non-prime-powers inclusive: %Y A375713 - terms: A361102 %Y A375713 - differences: A375708 %Y A375713 - runs: A373678, A373676, A373677, A110969 %Y A375713 - antiruns: A373679, A373575, A255346, A373672 %Y A375713 A000040 lists all of the primes, differences A001223. %Y A375713 A007916 lists non-perfect-powers, differences A375706. %Y A375713 Cf. A046933, A053289, A073783, A093555, A176246, A251092, A375714. %K A375713 nonn %O A375713 1,1 %A A375713 _Gus Wiseman_, Sep 02 2024