login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

Number of base 12 circular n-digit numbers with adjacent digits differing by 8 or less.
0

%I #14 Jul 18 2017 01:46:12

%S 1,12,132,1380,15260,169252,1879782,20881502,231972500,2577002988,

%T 28628206202,318033966218,3533075401202,39249335918974,

%U 436025331971998,4843854954088810,53810935050499732,597791791563925916

%N Number of base 12 circular n-digit numbers with adjacent digits differing by 8 or less.

%C [Empirical] a(base,n)=a(base-1,n)+F(8) for base>=8.int(n/2)+1 and F(d) is the largest coefficient in (1+x+...+x^(2d))^n.

%F G.f.: (1-6*x^2-88*x^3+15*x^4+128*x^5-5*x^6-36*x^7) / ((1-2*x-x^2+x^3)*(1-10*x-13*x^2+7*x^3+6*x^4)) (conjectured). - _Colin Barker_, Jul 17 2017

%o (S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-1](($[i]`-$[(i+1)mod N]`>8)+($[(i+1)mod N]`-$[i]`>8))

%K nonn,base

%O 0,2

%A _R. H. Hardin_, Dec 28 2006