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 A192321 #30 Jun 13 2017 16:39:04 %S A192321 6,14,15,21,33,38,57,62,69,77,111,119,141,143,155,161,194,203,206,209, %T A192321 215,218,278,287,309,314,329,381,395,398,447,453,489,533,537,551,554, %U A192321 566,579,626,635,671,755,785,818,878,899,959,974,993,1007,1011,1041,1067,1077,1133,1142,1149,1191,1202,1263 %N A192321 Semiprime numbers n such that n^2 + n + 1 is prime. %H A192321 Harvey P. Dale, <a href="/A192321/b192321.txt">Table of n, a(n) for n = 1..1000</a> %e A192321 309 is in the sequence because 309 is semiprime (309 = 3 * 103) and 309^2 + 309 + 1 = 95791 is prime. %t A192321 Select[Range[2000],PrimeOmega[#]==2&&PrimeQ[#^2+#+1]&] (* _Harvey P. Dale_, Feb 26 2013 *) %o A192321 (PARI) issemi(n)=bigomega(n)==2 %o A192321 is(n)=isprime(n^2+n+1) && issemi(n) \\ _Charles R Greathouse IV_, Jun 13 2017 %Y A192321 Intersection of A182253 and A001358. %Y A192321 Subsequence of A182253. %K A192321 nonn,easy %O A192321 1,1 %A A192321 _Jonathan Vos Post_, Dec 19 2012