A124893 Number of base 15 circular n-digit numbers with adjacent digits differing by 2 or less.

1, 15, 69, 255, 1097, 4765, 21237, 95873, 437537, 2012997, 9321899, 43397633, 202926209, 952396005, 4484003747, 21168581905, 100170213121, 474981809053, 2256307682541, 10735210220803, 51148724456627, 244007372314919

Offset

0,2

Comments

[Empirical] a(base,n)=a(base-1,n)+A005191(n+1) for base>=2.int(n/2)+1.

See A285280 for confirmation of linear recurrence and code to produce sequence. - Ray Chandler, Aug 12 2023.

Links

Ray Chandler, Table of n, a(n) for n = 0..99

Index entries for linear recurrences with constant coefficients, signature (15, -78, 130, 176, -682, 44, 1128, -330, -818, 249, 261, -62, -30, 3, 1).

Prog

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

Crossrefs

Cf. Row 15 of A285280.

Sequence in context: A201126 A085474 A212109 * A352941 A126402 A053134

Adjacent sequences: A124890 A124891 A124892 * A124894 A124895 A124896

Keyword

nonn,base

Author

R. H. Hardin, Dec 28 2006

Status

approved