Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #10 Aug 12 2023 11:11:42
%S 1,23,109,407,1777,7813,35245,160953,742857,3455597,16177459,76129593,
%T 359815609,1706868797,8122449787,38757778297,185382123417,
%U 888570946797,4267072020187,20525592779337,98881792935527,477011872851207
%N Number of base 23 circular n-digit numbers with adjacent digits differing by 2 or less.
%C [Empirical] a(base,n)=a(base-1,n)+A005191(n+1) for base>=2.int(n/2)+1.
%C See A285280 for confirmation of linear recurrence and code to produce sequence. - _Ray Chandler_, Aug 12 2023.
%H Ray Chandler, <a href="/A124951/b124951.txt">Table of n, a(n) for n = 0..99</a>
%H <a href="/index/Rec#order_21">Index entries for linear recurrences with constant coefficients</a>, signature (23, -210, 910, -1406, -2888, 13004, -5440, -35735, 37373, 49139, -71097, -38050, 68300, 16925, -36185, -4145, 10375, 500, -1450, -25, 75).
%o (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))
%Y Cf. Row 23 of A285280.
%K nonn,base
%O 0,2
%A _R. H. Hardin_, Dec 28 2006