A125475 Number of base 18 circular n-digit numbers with adjacent digits differing by 9 or less.

1, 18, 252, 3168, 44472, 634368, 9124092, 131601852, 1900243080, 27449395092, 396572715092, 5729777752772, 82786984432932, 1196161590550776, 17282993079833922, 249717254801438778, 3608098064502340024

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..16.

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: A144708 A020528 A088924 * A255371 A016175 A062141

Adjacent sequences: A125472 A125473 A125474 * A125476 A125477 A125478

Keyword

nonn,base

Author

R. H. Hardin, Dec 28 2006

Status

approved