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 A257559 #10 Jul 10 2015 19:23:28
%S A257559 4,6,9,14,21,33,46,62,82,106,133,161,194,235,278,323,371,422,478,535,
%T A257559 597,662,731,802,878,955,1037,1121,1207,1294,1382,1473,1565,1658,1754,
%U A257559 1851,1954,2059,2165,2279,2395,2513,2638,2771,2906,3043
%N A257559 The slowest increasing sequence of semiprimes with strictly increasing difference of successive terms.
%C A257559 Semiprime analog of A070865.
%C A257559 Heuristically a(n) is around n^2 log n/log log n. - _Charles R Greathouse IV_, May 01 2015
%H A257559 Zak Seidov, <a href="/A257559/b257559.txt">Table of n, a(n) for n = 1..1000</a>
%F A257559 a(n) >> n^2. - _Charles R Greathouse IV_, Apr 30 2015
%o A257559 (PARI) issemi(n)=bigomega(n)==2
%o A257559 t=0; print1(last=4); while(1, n=last+t; while(!issemi(n++),); print1(", "n); t=n-last; last=n) \\ _Charles R Greathouse IV_, Apr 30 2015
%Y A257559 Cf. A001358, A070865.
%K A257559 nonn
%O A257559 1,1
%A A257559 _Zak Seidov_, Apr 30 2015