A125456 Number of base 21 circular n-digit numbers with adjacent digits differing by 8 or less.

1, 21, 285, 3333, 44589, 609441, 8484027, 119207781, 1683956109, 23857954869, 338563579455, 4808766812871, 68334330572247, 971314874179749, 13808436456553037, 196319581589707923, 2791268881281069805

Offset

0,2

Comments

[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

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]`-$[(i+1)mod N]`>8)+($[(i+1)mod N]`-$[i]`>8))

Crossrefs

Sequence in context: A028033 A176711 A025987 * A296333 A028028 A296633

Adjacent sequences: A125453 A125454 A125455 * A125457 A125458 A125459

Keyword

nonn,base

Author

R. H. Hardin, Dec 28 2006

Status

approved