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 A372686 #11 May 15 2024 06:57:40 %S A372686 1,2,4,9,11,31,64,76,167,309,502,801,1028,6363,7281,12079,12251,43237, %T A372686 43390,146605,291640,951351,1046198,2063216,3957778,11134645,14198321, %U A372686 28186247,54387475,105097565,249939829,393248783,751545789,1391572698,2182112798,8242984130 %N A372686 Sorted list of positions of first appearances in A014499 (number of ones in binary expansion of each prime). %C A372686 The unsorted version is A372517. %H A372686 Wikipedia, <a href="https://en.wikipedia.org/wiki/Hamming_weight">Hamming weight</a>. %F A372686 prime(a(n)) = A372685(n). %e A372686 The sequence contains 9 because the first 9 terms of A014499 are 1, 2, 2, 3, 3, 3, 2, 3, 4, and the last of these is the first position of 4. %t A372686 First/@GatherBy[Range[1000],DigitCount[Prime[#],2,1]&] %Y A372686 Positions of first appearances in A014499. %Y A372686 The unsorted version is A372517. %Y A372686 For binary length we have A372684, primes A104080, firsts of A035100. %Y A372686 Taking primes gives A372685, unsorted version A061712. %Y A372686 A000120 counts ones in binary expansion (binary weight), zeros A080791. %Y A372686 A029837 gives greatest binary index, least A001511. %Y A372686 A030190 gives binary expansion, reversed A030308. %Y A372686 A035103 counts zeros in binary expansion of each prime, firsts A372474. %Y A372686 A048793 lists binary indices, reverse A272020, sum A029931. %Y A372686 A070939 gives length of binary expansion (number of bits). %Y A372686 A372471 lists binary indices of primes. %Y A372686 Cf. A000040, A005940, A059015, A066195, A069010, A071814, A211997, A372429, A372433, A372473, A372516. %K A372686 nonn,base %O A372686 1,2 %A A372686 _Gus Wiseman_, May 14 2024 %E A372686 a(26)-a(36) from _Pontus von Brömssen_, May 15 2024