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 A180748 #10 Dec 23 2019 06:04:45 %S A180748 5,8,10,11,12,14,20,24,27,29,30,32,33,35,36,37,40,41,43,44,45,46,48, %T A180748 49,52,53,54,57,61,64,66,71,73,74,77,83,84,85,86,87,92,93,94,96,97,98, %U A180748 99,104,105,109,113,114,115,116,121,123,124,125,126,127,128,130,133,135 %N A180748 Numbers k such that k^2 - k + 1 is semiprime. %H A180748 Amiram Eldar, <a href="/A180748/b180748.txt">Table of n, a(n) for n = 1..10000</a> %t A180748 Select[Range[135], PrimeOmega[#^2 - # + 1] == 2 &] (* _Amiram Eldar_, Dec 23 2019 *) %Y A180748 Cf. A001358, A002061. %K A180748 easy,nonn %O A180748 1,1 %A A180748 _Jason Earls_, Sep 19 2010