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 A084572 #4 Mar 30 2012 18:36:34 %S A084572 1,2,5,11,19,31,53,89,149,239,379,599,941,1481,2333,3671,5779,9091, %T A084572 14281,22433,35251,55373,86981,136649,214651,337189,529657,832003, %U A084572 1306913,2052899,3224687,5065351,7956661,12498313,19632329,30838393 %N A084572 Let a(1)=1; for n>1, a(n)=nextprime((Pi/2)*a(n-1)). %o A084572 (PARI) a(n)=if(n<2,1,nextprime((Pi/2)*a(n-1))); for(n=1,50,print1(a(n),",")) %Y A084572 Cf. A084571. %K A084572 nonn %O A084572 1,2 %A A084572 _Paul D. Hanna_, May 30 2003