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 A209623 #15 Jun 12 2014 13:03:36 %S A209623 7,13,19,23,31,37,43,47,53,61,67,73,79,83,89,97,103,109,113,127,131, %T A209623 151,157,163,167,173,193,199,211,223,229,233,251,257,263,271,277,293, %U A209623 307,313,317,331,349,353,359,367,373,379,383,389,397,401,433,439,443 %N A209623 Primes separated from their adjacent next primes by a prime number of successive composites. %C A209623 a(1) = 7 is the first prime separated from the next prime (11) by a prime number (3) of successive composites, namely, 8, 9, 10. %H A209623 K. D. Bajpai, <a href="/A209623/b209623.txt">Table of n, a(n) for n = 1..8000</a> %t A209623 Select[Prime[Range[100]], PrimeQ[NextPrime[#] - # - 1] &] (* _T. D. Noe_, Mar 12 2012 *) %Y A209623 Cf. A046933, A209618, A098015. %K A209623 nonn %O A209623 1,1 %A A209623 _Lekraj Beedassy_, Mar 10 2012