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 A125025 #24 Aug 15 2021 10:07:22 %S A125025 3,8,3,8,3 %N A125025 Lengths of rows in A124570. %C A125025 This sequence is to A124570 as A123556 is to A124064. %C A125025 a(n) is at most A053669(n)^2, with equality if and only if A053669(n)^2 is the first semiprime in the corresponding arithmetic progression. - _Charlie Neder_, Jan 10 2019 %C A125025 By subsampling a given arithmetic progression with k terms and distance d one may generate an arithmetic progression of a larger distance d*b, b=1,2,3...., with 1+(k-1)/b terms: a(b*n) >= 1+floor( (a(n)-1)/b ), b=1,2,3..... - _R. J. Mathar_, Aug 02 2021 %C A125025 18 <= a(6) <= 24. - _Jinyuan Wang_, Aug 06 2021 %C A125025 a(12) >= 17. a(18) >= 18. a(24) >= 18. a(30) >= 21. a(36) >= 19. a(42) >= 20. a(6006) >= 24 (starting 652744562555081). _Hugo van der Sanden_, Aug 14 2021 %Y A125025 Cf. A001358, A123556, A124064, A124570, A091016 (for n=6). %K A125025 nonn,hard,more %O A125025 1,1 %A A125025 _Jonathan Vos Post_, Nov 15 2006