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 A373678 #10 Jun 17 2024 14:48:34 %S A373678 1,6,10,12,29,18,63,24,26,28,30,138,117,42,135,48,153,280,60,125,131, %T A373678 207,72,380,80,82,430,651,297,102,315,108,333,819,369,126,259,670,138, %U A373678 1296,150,770,800,495,168,513,880,180,1674,192,585,198,2255,2387,675 %N A373678 Sums of maximal runs of non-prime-powers. %C A373678 We consider 1 to be a power of a prime and a non-prime-power, but not a prime-power. %C A373678 A run of a sequence (in this case A361102) is an interval of positions at which consecutive terms differ by one. %H A373678 Gus Wiseman, <a href="/A373403/a373403.txt">Four statistics for runs and antiruns of prime, nonprime, squarefree, and nonsquarefree numbers</a>. %e A373678 The maximal runs of non-powers of primes begin: %e A373678 1 %e A373678 6 %e A373678 10 %e A373678 12 %e A373678 14 15 %e A373678 18 %e A373678 20 21 22 %e A373678 24 %e A373678 26 %e A373678 28 %e A373678 30 %e A373678 33 34 35 36 %e A373678 38 39 40 %e A373678 42 %e A373678 44 45 46 %e A373678 48 %e A373678 50 51 52 %e A373678 54 55 56 57 58 %e A373678 60 %t A373678 Total/@Split[Select[Range[100],!PrimePowerQ[#]&],#1+1==#2&]//Most %Y A373678 A000040 lists the primes, differences A001223. %Y A373678 A000961 lists all powers of primes (A246655 if not including 1). %Y A373678 A025528 counts prime-powers up to n. %Y A373678 A057820 gives first differences of consecutive prime-powers, gaps A093555. %Y A373678 A361102 lists all non-prime-powers (A024619 if not including 1). %Y A373678 See link for composite, prime, nonsquarefree, and squarefree runs. %Y A373678 Prime-power runs: A373675, min A373673, max A373674, length A174965. %Y A373678 Non-prime-power runs: A373678, min A373676, max A373677, length A110969. %Y A373678 Prime-power antiruns: A373576, min A120430, max A006549, length A373671. %Y A373678 Non-prime-power antiruns: A373679, min A373575, max A255346, length A373672. %Y A373678 Cf. A005117, A014963, A038664, A046933, A054265, A065855, A071148, A293697, A371201, A373400. %K A373678 nonn %O A373678 1,2 %A A373678 _Gus Wiseman_, Jun 16 2024