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%I #14 Jun 03 2017 13:03:37
%S 1,8,58,398,2902,21238,155716,1142016,8376142,61435910,450611298,
%T 3305081546,24241659940,177804417188,1304135570978,9565395603838,
%U 70158958263262,514592352357838,3774361758858916,27683673535999896
%N Number of base 8 circular n-digit numbers with adjacent digits differing by 5 or less.
%C [Empirical] a(base,n)=a(base-1,n)+F(5) for base>=5.int(n/2)+1 and F(d) is the largest coefficient in (1+x+...+x^(2d))^n.
%F G.f.: (1 - 3*x^2 - 28*x^3 + 3*x^4 + 16*x^5) / ((1 - x - x^2)*(1 - 7*x - 3*x^2 + 4*x^3)) (conjectured). - _Colin Barker_, Jun 03 2017
%o (S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-1](($[i]`-$[(i+1)mod N]`>5)+($[(i+1)mod N]`-$[i]`>5))
%K nonn,base
%O 0,2
%A _R. H. Hardin_, Dec 28 2006