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 A126365 #8 Nov 26 2012 11:54:25
%S A126365 1,11,31,89,257,745,2165,6303,18375,53625,156629,457795,1338779,
%T A126365 3916897,11463989,33563035,98286811,287884769,843365485,2471005371,
%U A126365 7240717539,21219286113,62189049541,182274146987,534268171099
%N A126365 Number of base 11 n-digit numbers with adjacent digits differing by one or less.
%C A126365 [Empirical] a(base,n)=a(base-1,n)+3^(n-1) for base>=n; a(base,n)=a(base-1,n)+3^(n-1)-2 when base=n-1
%F A126365 Empirical G.f.: -(6*x^6+4*x^5-34*x^4-6*x^3+26*x^2-5*x-1) / ((x^2+2*x-1)*(2*x^4-4*x^3-2*x^2+4*x-1)). [_Colin Barker_, Nov 26 2012]
%o A126365 (S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-2](($[i]`-$[i+1]`>1)+($[i+1]`-$[i]`>1))
%K A126365 nonn,base
%O A126365 0,2
%A A126365 _R. H. Hardin_, Dec 26 2006