%I #11 Jun 03 2017 13:02:27
%S 1,8,52,308,2012,13308,88582,590710,3941716,26308100,175600282,
%T 1172118538,7823866514,52224288462,348597313326,2326889050098,
%U 15531999290132,103676198275324,692039319384424,4619367120609720
%N Number of base 8 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
%F G.f.: (1 - 6*x^2 - 40*x^3 + 15*x^4 + 48*x^5 - 5*x^6 - 12*x^7) / ((1 - 2*x - x^2 + x^3)*(1 - 6*x - 5*x^2 + 3*x^3 + 2*x^4)) (conjectured). - _Colin Barker_, Jun 03 2017
%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
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