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 A101779 #11 Mar 31 2012 10:26:44 %S A101779 2,2,3,5,5,154769,2894219,2894219,407874179,214580145779, %T A101779 9448481062019,247236503934419,2545206711847799,18178612369988250179, %U A101779 53792264108455702829 %N A101779 a(n) = least k such that all of k, 2k+1, 3k+2, ..., nk+n-1 are primes, or 0 if no such k is found. %C A101779 a(10) > 3691000000, _Robert G. Wilson v_, Mar 23 2007 %C A101779 By definition the same as A088651(n)-1 if k exists. It is conjectured k always exists. - a(10)-a(15) from _Jens Kruse Andersen_, May 02 2008 %t A101779 f[1] = 2; f[n_] := f[n] = Block[{k = PrimePi@ f[n - 1], p, t = Table[i*p + (i - 1), {i, 2, n}]}, While[p = Prime@k; Union@PrimeQ@t != {True}, k++ ]; p]; Do[ Print[f@n // Timing], {n, 10}] (* _Robert G. Wilson v_, Mar 23 2007 *) %Y A101779 Cf. A000040, A005384, A067256, A067257, A067258, A101767, A101768, A101769, A101770. %Y A101779 Cf. A088651. %K A101779 nonn %O A101779 1,1 %A A101779 _Jonathan Vos Post_ and _Ray Chandler_, Jan 13 2005 %E A101779 a(10)-a(15) from _Jens Kruse Andersen_, May 02 2008