%I #5 Mar 31 2012 12:35:05
%S 1,23,67,197,581,1717,5081,15051,44619,132357,392825,1166383,3464543,
%T 10294187,30595831,90958325,270471141,804429189,2392956009,7119580287,
%U 21185591199,63050397375,187668462027,558658899825,1663222335825
%N Number of base 23 n-digit numbers with adjacent digits differing by one or less.
%C [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
%o (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 nonn,base
%O 0,2
%A _R. H. Hardin_, Dec 26 2006
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