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 A248391 #7 Oct 14 2023 11:11:11 %S A248391 15,14,85,57,161,319,403,259,451,559,235,901,177,1159,1541,781,2117, %T A248391 1027,2573,445,1649,1121,122,707,851,1133,2911,3103,1417,3397,3503, %U A248391 415,4183,2159,5141,393,2603,244,973,2323,5513,10117,4223,4553,11899,2171,7439,5549,8507,3247,6731,579,2489,8083,1379,3197 %N A248391 Terms in A247665 which are neither primes nor prime powers, in order of appearance. %H A248391 Russ Cox and N. J. A. Sloane, <a href="/A248391/b248391.txt">Table of n, a(n) for n = 1..374</a> %Y A248391 Cf. A247665, A247885, A248379, A248387-A248390. %K A248391 nonn %O A248391 1,1 %A A248391 _Russ Cox_ and _N. J. A. Sloane_, Oct 16 2014