A125318 Number of base 8 circular n-digit numbers with adjacent digits differing by 3 or less.

1, 8, 44, 212, 1156, 6428, 36338, 206942, 1183164, 6777860, 38866134, 222980282, 1279588414, 7343932838, 42151639560, 241943513252, 1388738207756, 7971319975484, 45755345035400, 262636025020328, 1507534275820126

Offset

0,2

Comments

[Empirical] a(base,n)=a(base-1,n)+A025012(n+1) for base>=3.int(n/2)+1

Links

Table of n, a(n) for n=0..20.

Formula

G.f.: (1 - 10*x^2 - 40*x^3 + 45*x^4 + 48*x^5 - 35*x^6 - 12*x^7 + 7*x^8) / ((1 + x)*(1 - 3*x + x^3)*(1 - 6*x + x^2 + 3*x^3 - x^4)) (conjectured). - Colin Barker, Jun 03 2017

Prog

(S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-1](($[i]`-$[(i+1)mod N]`>3)+($[(i+1)mod N]`-$[i]`>3))

Crossrefs

Sequence in context: A271813 A270678 A292487 * A000373 A176688 A272154

Adjacent sequences: A125315 A125316 A125317 * A125319 A125320 A125321

Keyword

nonn,base

Author

R. H. Hardin, Dec 28 2006

Status

approved