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 A263896 #20 Nov 30 2015 16:07:43 %S A263896 1,6,15,28,90,66,91,285,153,190,588,276,800,972,435,496,1485,1750,703, %T A263896 2223,861,989,3060,1175,3136,3723,1431,4290,4731,1829,2257,6489,6175, %U A263896 2747,6831,2627,2993,9150,8547,4187,10044,3901,10795,11223,7921,11830,12741 %N A263896 Central terms of triangle in A075383. %C A263896 a(n) = A075383(2*n-1,n). %o A263896 (Haskell) %o A263896 a263896 n = a075383 (2 * n - 1) n %Y A263896 Cf. A075383. %K A263896 nonn %O A263896 1,2 %A A263896 _Reinhard Zumkeller_, Nov 29 2015