A126518 Number of base 23 n-digit numbers with adjacent digits differing by four or less.

1, 23, 187, 1563, 13187, 111855, 951843, 8116589, 69304469, 592275463, 5064405547, 43320119881, 370639572699, 3171604704237, 27142404725961, 232297572817893, 1988192727095313, 17017021355308651, 145651801767851231

Offset

0,2

Comments

[Empirical] a(base,n)=a(base-1,n)+9^(n-1) for base>=4n-3; a(base,n)=a(base-1,n)+9^(n-1)-2 when base=4n-4

Links

Table of n, a(n) for n=0..18.

Prog

(S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-2](($[i]`-$[i+1]`>4)+($[i+1]`-$[i]`>4))

Crossrefs

Cf. Base 23 differing by three or less A126491, two or less A126410, one or less A126377.

Sequence in context: A302200 A269072 A125360 * A167467 A129052 A201859

Adjacent sequences: A126515 A126516 A126517 * A126519 A126520 A126521

Keyword

nonn,base

Author

R. H. Hardin, Dec 28 2006

Status

approved