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 A321488 #7 Nov 14 2018 13:39:55 %S A321488 2057,2873,3689,4015,4991,6137,6851,9401,10795,11033,11501,11837, %T A321488 11849,12341,12593,13481,13795,14297,15113,15695,17155,17633,18011, %U A321488 18377,18469,18941,19097,20009,21463,21641,22661,22919,23273,24089,24521,25721,25993,26381 %N A321488 Nonsemiprimes in A306097 = A121707 \ A267999. %C A321488 Equivalently, terms of A321487 not in A267999, or intersection of A321487 and A306097. %H A321488 M. F. Hasler, <a href="/A321488/b321488.txt">Table of n, a(n) for n = 1..100</a> %Y A321488 Cf. A306097 = A121707 \ A267999, A321487 \ A267999, A321487 n A306097. %K A321488 nonn %O A321488 1,1 %A A321488 _M. F. Hasler_, Nov 11 2018