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 A257560 #9 May 01 2015 10:37:45 %S A257560 2,3,5,7,12,13,16,20,24,27,28,33,41,43,45,48,51,56,57,62,65,69,71,76, %T A257560 77,82,84,86,87,88,91,92,93,96,97,103,105,106,114,116,118,125,133,135, %U A257560 137,140,143,147,149,155,158,162,165,167,172,176,177,183 %N A257560 First differences of A257559. %C A257560 By definition this sequence is strictly increasing. Heuristically a(n) is around 2n log n/log log n. - _Charles R Greathouse IV_, May 01 2015 %H A257560 Zak Seidov, <a href="/A257560/b257560.txt">Table of n, a(n) for n = 1..1000</a> %F A257560 a(n) = A257559(n+1) - A257559(n). %o A257560 (PARI) issemi(n)=bigomega(n)==2 %o A257560 t=0; v=List(); last=4; while(1, n=last+t; while(!issemi(n++), ); listput(v, t=n-last); if(v==100, return(Set(v))); last=n) \\ _Charles R Greathouse IV_, May 01 2015 %Y A257560 Cf. A257559. %K A257560 nonn %O A257560 1,1 %A A257560 _Zak Seidov_, Apr 30 2015