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 A188225 #11 May 16 2018 09:29:29 %S A188225 2,31,256,1496,6936,27132,93024,286824,810084,2124694,5230016, %T A188225 12183560,27041560,57500460,117675360,232676280,445962870,830905245, %U A188225 1508593920,2674776720,4639918800,7887861960,13160496960,21578373360,34810394760 %N A188225 Number of ways to select 15 knights from n knights sitting at a round table if no adjacent knights are chosen. %F A188225 a(n) = C(n - 15, 15) + C(n - 16, 14) %e A188225 For n = 30 a(30) = C(15, 15) + C(14, 14) = 2 %t A188225 Table[Binomial[n-15,15]+Binomial[n-16,14],{n,30,60}] (* _Harvey P. Dale_, May 16 2018 *) %Y A188225 a(n) = A010968(n - 15) + A010967(n - 16) %K A188225 nonn %O A188225 30,1 %A A188225 _Zoltán Lőrincz_, Mar 30 2011