A126541 Number of base 20 n-digit numbers with adjacent digits differing by five or less.

1, 20, 190, 1870, 18600, 185922, 1862204, 18667904, 187205534, 1877615174, 18833087302, 188906865160, 1894866747430, 19006912484080, 190653725780160, 1912402757442222, 19182869344924714, 192418948095124214

Offset

0,2

Comments

[Empirical] a(base,n)=a(base-1,n)+11^(n-1) for base>=5n-4; a(base,n)=a(base-1,n)+11^(n-1)-2 when base=5n-5

Links

Table of n, a(n) for n=0..17.

Prog

(S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-2](($[i]`-$[i+1]`>5)+($[i+1]`-$[i]`>5))

Crossrefs

Cf. Base 20 differing by four or less A126515, three or less A126488, two or less A126407, one or less A126374.

Sequence in context: A171075 A061180 A125383 * A213218 A247742 A355590

Adjacent sequences: A126538 A126539 A126540 * A126542 A126543 A126544

Keyword

nonn,base

Author

R. H. Hardin, Dec 28 2006

Status

approved