A126537 - OEIS

A126537

Number of base 16 n-digit numbers with adjacent digits differing by five or less.

1, 16, 146, 1386, 13276, 127470, 1224594, 11766272, 113057850, 1086341506, 10438376428, 100299731078, 963754991066, 9260480594912, 88981641951426, 855002344551114, 8215503709753468, 78940720623107646, 758521643084139202

(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..18.

FORMULA

G.f.: (1+5*x-21*x^2-30*x^3+44*x^4+20*x^5-20*x^6) / (1-11*x+9*x^2+46*x^3-36*x^4-28*x^5+20*x^6) (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 16 differing by four or less A126511, three or less A126484, two or less A126403, one or less A126370.

Sequence in context: A027651 A125379 A232063 * A252818 A232957 A214513

Adjacent sequences: A126534 A126535 A126536 * A126538 A126539 A126540

KEYWORD

nonn,base

AUTHOR

R. H. Hardin, Dec 28 2006

STATUS

approved