A125407 Number of base 19 circular n-digit numbers with adjacent digits differing by 6 or less.

1, 19, 205, 1867, 19609, 210299, 2304745, 25570683, 286088961, 3218305099, 36333221305, 411138068195, 4659331066705, 52854308911787, 599940896079401, 6812571733982387, 77379505012100545, 879048702969334779

Offset

0,2

Comments

[Empirical] a(base,n)=a(base-1,n)+F(6) for base>=6.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.

Prog

(S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-1](($[i]`-$[(i+1)mod N]`>6)+($[(i+1)mod N]`-$[i]`>6))

Crossrefs

Sequence in context: A085770 A002501 A180364 * A289423 A278556 A023017

Adjacent sequences: A125404 A125405 A125406 * A125408 A125409 A125410

Keyword

nonn,base

Author

R. H. Hardin, Dec 28 2006

Status

approved