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A125469 Number of base 12 circular n-digit numbers with adjacent digits differing by 9 or less. 0
1, 12, 138, 1542, 17782, 205222, 2369460, 27358168, 315883982, 3647274798, 42112344498, 486239639898, 5614244249860, 64823465468332, 748467912775938, 8641997344805782, 99782658458533982, 1152115481155283262 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

[Empirical] a(base,n)=a(base-1,n)+F(9) for base>=9.int(n/2)+1 and F(d) is the largest coefficient in (1+x+...+x^(2d))^n.

LINKS

Table of n, a(n) for n=0..17.

FORMULA

G.f.: (1-3*x^2-52*x^3+3*x^4+32*x^5) / ((1-x-x^2)*(1-11*x-7*x^2+8*x^3)) (conjectured). - Colin Barker, Jul 17 2017

PROG

(S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-1](($[i]`-$[(i+1)mod N]`>9)+($[(i+1)mod N]`-$[i]`>9))

CROSSREFS

Sequence in context: A059517 A243966 A097167 * A113366 A003379 A281247

Adjacent sequences:  A125466 A125467 A125468 * A125470 A125471 A125472

KEYWORD

nonn,base

AUTHOR

R. H. Hardin, Dec 28 2006

STATUS

approved

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Last modified March 4 05:42 EST 2021. Contains 341779 sequences. (Running on oeis4.)