A126514 Number of base 19 n-digit numbers with adjacent digits differing by four or less.

1, 19, 151, 1239, 10271, 85611, 715649, 5991499, 50202083, 420816645, 3528266989, 29585656541, 248100670697, 2080601208199, 17448464481771, 146328696766445, 1227167540644629, 10291514720245361, 86308846158006385

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 19 differing by three or less A126487, two or less A126406, one or less A126373.

Sequence in context: A293116 A066668 A111884 * A168025 A160431 A010825

Adjacent sequences: A126511 A126512 A126513 * A126515 A126516 A126517

Keyword

nonn,base

Author

R. H. Hardin, Dec 28 2006

Status

approved