A125484 - OEIS

%I #8 Mar 31 2012 12:35:02

%S 1,27,423,5607,85683,1337727,21331503,344238579,5599424547,

%T 91540779903,1501346684863,24673460611915,406009294231251,

%U 6686397678162879,110171301582051951,1815861973753907787,29935310771775478339

%N Number of base 27 circular n-digit numbers with adjacent digits differing by 9 or less.

%C [Empirical] a(base,n)=a(base-1,n)+F(9) for base>=9.int(n/2)+1 and F(d) is the largest coefficient in (1+x+...+x^(2d))^n

%o (S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-1](($[i]`-$[(i+1)mod N]`>9)+($[(i+1)mod N]`-$[i]`>9))

%K nonn,base

%O 0,2

%A _R. H. Hardin_, Dec 28 2006