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 A221533 #41 Aug 04 2018 03:23:08
%S A221533 1,9,18,33,57,60,84,141,147,187,245,265,330,417,421,430,551,620,683,
%T A221533 837,791,865,1056,1044,1182,1288,1278,1506,1737,1677,1685,1983,2097,
%U A221533 2228,2517,2433,2423,2780,2926,3079,3253,3216,3563,3733,3713,3872,4249,4318
%N A221533 a(n) is the number of integers of the form binomial(4*n^2 - k - 2, k - 1) / k, k=3, 4, ... , 2*n^2 - 2, n >= 2.
%H A221533 Peter J. C. Moses, <a href="/A221533/b221533.txt">Table of n, a(n) for n = 2..301</a>
%F A221533 If (2n-1, 2n+1) is a pair of twin primes, then a(n) = 2*n^2 - 2*n - 3.
%t A221533 Table[Count[Table[Binomial[4*n^2-k-2,k-1]/k, {k,3,2*n^2-2}], _Integer], {n, 2, 30}] (* _Peter J. C. Moses_, Aug 17 2013 *)
%Y A221533 Cf. A177501.
%K A221533 nonn
%O A221533 2,2
%A A221533 _Vladimir Shevelev_, Aug 17 2013
%E A221533 More terms from _Peter J. C. Moses_, Aug 17 2013