A125388 Number of base 25 circular n-digit numbers with adjacent digits differing by 5 or less.

1, 25, 245, 1945, 18025, 169975, 1641629, 16074699, 159107841, 1587693061, 15944909855, 160952971853, 1631461695001, 16593111357549, 169235353884807, 1730038601905255, 17719417102045601, 181773198890744037

Offset

0,2

Comments

[Empirical] a(base,n)=a(base-1,n)+F(5) for base>=5.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]`-$[(i+1)mod N]`>5)+($[(i+1)mod N]`-$[i]`>5))

Crossrefs

Sequence in context: A362393 A380923 A107943 * A126546 A023073 A022685

Adjacent sequences: A125385 A125386 A125387 * A125389 A125390 A125391

Keyword

nonn,base

Author

R. H. Hardin, Dec 28 2006

Status

approved