A126538 - OEIS

A126538

Number of base 17 n-digit numbers with adjacent digits differing by five or less.

1, 17, 157, 1507, 14607, 142041, 1382455, 13458785, 131037075, 1275829041, 12422061043, 120947162241, 1177600426155, 11465692698745, 111635587544291, 1086938653558289, 10582966126771531, 103040932264504713

(list; graph; refs; listen; history; text; internal format)

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.

FORMULA

G.f.: (1+6*x-24*x^2-54*x^3+42*x^4+72*x^5-16*x^6-24*x^7) / (1-11*x+6*x^2+64*x^3-18*x^4-76*x^5+8*x^6+24*x^7) (conjectured). - Colin Barker, Jul 18 2017

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 17 differing by four or less A126512, three or less A126485, two or less A126404, one or less A126371.

Sequence in context: A176838 A176622 A125380 * A164746 A198859 A160295

Adjacent sequences: A126535 A126536 A126537 * A126539 A126540 A126541

KEYWORD

nonn,base

AUTHOR

R. H. Hardin, Dec 28 2006

STATUS

approved