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 A074268 #20 Sep 22 2015 15:09:27 %S A074268 3,7,43,157,4423,6163,19183,22651,26407,37057,113233,121453,143263, %T A074268 208393,292141,375157,412807,527803,590593,843643,981091,1041421, %U A074268 1193557,1246573,1441201,1514131,1905781,2023507,2397853,2453923,2548813,2626021,2864557 %N A074268 Primes of the form p^2 - p + 1 where p is prime. %C A074268 Note that p^2 - p + 1 = p * phi(p) + 1 when p is prime. %H A074268 Vincenzo Librandi, <a href="/A074268/b074268.txt">Table of n, a(n) for n = 1..1000</a> %t A074268 Select[Table[p = Prime[n]; p*EulerPhi[p] + 1, {n, 270}], PrimeQ] (* _Arkadiusz Wesolowski_, Dec 13 2011 *) %t A074268 Select[Table[p^2-p+1,{p,Prime[Range[300]]}],PrimeQ] (* _Harvey P. Dale_, Sep 22 2015 *) %Y A074268 Cf. A065508 (values of p). %K A074268 nonn,easy %O A074268 1,1 %A A074268 _Enoch Haga_, Jan 16 2004