A126412 Number of base 25 n-digit numbers with adjacent digits differing by two or less.

1, 25, 119, 575, 2793, 13611, 66473, 325149, 1592355, 7805655, 38292485, 187972885, 923231055, 4536538325, 22300261185, 109658861091, 539395083843, 2653895007787, 13060517277349, 64287300999691, 316495856518423

Offset

0,2

Comments

[Empirical] a(base,n)=a(base-1,n)+5^(n-1) for base>=2n-1; a(base,n)=a(base-1,n)+5^(n-1)-2 when base=2n-2

Links

Table of n, a(n) for n=0..20.

Prog

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

Crossrefs

Cf. Base 25 differing by one or less A126379.

Sequence in context: A218493 A360511 A124953 * A078815 A270368 A206472

Adjacent sequences: A126409 A126410 A126411 * A126413 A126414 A126415

Keyword

nonn,base

Author

R. H. Hardin, Dec 28 2006

Status

approved