A126414 Number of base 27 n-digit numbers with adjacent digits differing by two or less.

1, 27, 129, 625, 3043, 14861, 72723, 356399, 1748605, 8586905, 42198735, 207504135, 1020887305, 5024819575, 24741667433, 121865892063, 600430229661, 2959070561939, 14586392574071, 71916648942815, 354642311037069

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 27 differing by one or less A126381.

Sequence in context: A267935 A048615 A124955 * A183427 A262852 A066414

Adjacent sequences: A126411 A126412 A126413 * A126415 A126416 A126417

Keyword

nonn,base

Author

R. H. Hardin, Dec 28 2006

Status

approved