%I #7 Mar 31 2012 12:35:02

%S 1,16,124,796,5924,44916,348652,2743036,21801764,174565444,1405459324,

%T 11362215276,92138276228,748875775404,6097017988948,49701864868956,

%U 405539673414148,3311264043438796,27050524930821556,221065493126829404

%N Number of base 16 circular n-digit numbers with adjacent digits differing by 4 or less.

%C [Empirical] a(base,n)=a(base-1,n)+A025014(n+1) for base>=4.int(n/2)+1

%o (S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-1](($[i]`-$[(i+1)mod N]`>4)+($[(i+1)mod N]`-$[i]`>4))

%K nonn,base

%O 0,2

%A _R. H. Hardin_, Dec 28 2006