A126401 Number of base 14 n-digit numbers with adjacent digits differing by two or less.

1, 14, 64, 300, 1418, 6736, 32098, 153274, 732980, 3508800, 16808758, 80562042, 386258512, 1852391310, 8885102252, 42623064868, 204486065796, 981089277884, 4707294583320, 22586391528066, 108375512842272, 520021938034950

Offset

0,2

Comments

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

Links

Table of n, a(n) for n=0..21.

Formula

G.f.: (1+6*x-35*x^2-13*x^3+63*x^4+18*x^5-17*x^6-4*x^7) / (1-8*x+13*x^2+17*x^3-25*x^4-12*x^5+7*x^6+2*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]`-$[i+1]`>2)+($[i+1]`-$[i]`>2))

Crossrefs

Cf. Base 14 differing by one or less A126368.

Sequence in context: A074354 A212743 A124892 * A275268 A304873 A226754

Adjacent sequences: A126398 A126399 A126400 * A126402 A126403 A126404

Keyword

nonn,base

Author

R. H. Hardin, Dec 28 2006

Status

approved