A125431 Number of base 19 circular n-digit numbers with adjacent digits differing by 7 or less.

1, 19, 229, 2371, 28117, 340639, 4206175, 52452531, 657946661, 8280460237, 104408596879, 1317891532471, 16644977894179, 210297040134369, 2657451892030143, 33584889901686421, 424471412263606133

Offset

0,2

Comments

[Empirical] a(base,n)=a(base-1,n)+F(7) for base>=7.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]`-$[(i+1)mod N]`>7)+($[(i+1)mod N]`-$[i]`>7))

Crossrefs

Sequence in context: A041688 A140843 A243420 * A104116 A028026 A135487

Adjacent sequences: A125428 A125429 A125430 * A125432 A125433 A125434

Keyword

nonn,base

Author

R. H. Hardin, Dec 28 2006

Status

approved