A126379 Number of base 25 n-digit numbers with adjacent digits differing by one or less.

1, 25, 73, 215, 635, 1879, 5567, 16509, 48993, 145479, 432191, 1284481, 3818837, 11357069, 33784477, 100524263, 299168955, 890522631, 2651236335, 7894421265, 23510114133, 70023966177, 208589168433, 621421019043, 1851508693479

Offset

0,2

Comments

[Empirical] a(base,n)=a(base-1,n)+3^(n-1) for base>=n; a(base,n)=a(base-1,n)+3^(n-1)-2 when base=n-1

Links

Table of n, a(n) for n=0..24.

Prog

(S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-2](($[i]`-$[i+1]`>1)+($[i+1]`-$[i]`>1))

Crossrefs

Sequence in context: A337156 A069190 A124718 * A114553 A098439 A318643

Adjacent sequences: A126376 A126377 A126378 * A126380 A126381 A126382

Keyword

nonn,base

Author

R. H. Hardin, Dec 26 2006

Status

approved