A124951 Number of base 23 circular n-digit numbers with adjacent digits differing by 2 or less.

1, 23, 109, 407, 1777, 7813, 35245, 160953, 742857, 3455597, 16177459, 76129593, 359815609, 1706868797, 8122449787, 38757778297, 185382123417, 888570946797, 4267072020187, 20525592779337, 98881792935527, 477011872851207

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 (23, -210, 910, -1406, -2888, 13004, -5440, -35735, 37373, 49139, -71097, -38050, 68300, 16925, -36185, -4145, 10375, 500, -1450, -25, 75).

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 23 of A285280.

Sequence in context: A176928 A157607 A142272 * A126410 A356877 A260986

Adjacent sequences: A124948 A124949 A124950 * A124952 A124953 A124954

Keyword

nonn,base

Author

R. H. Hardin, Dec 28 2006

Status

approved