This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A124951 #12 Apr 30 2025 14:50:56
%S A124951 1,23,109,407,1777,7813,35245,160953,742857,3455597,16177459,76129593,
%T A124951 359815609,1706868797,8122449787,38757778297,185382123417,
%U A124951 888570946797,4267072020187,20525592779337,98881792935527,477011872851207
%N A124951 Number of base 23 circular n-digit numbers with adjacent digits differing by 2 or less.
%C A124951 [Empirical] a(base,n)=a(base-1,n)+A005191(n+1) for base>=2.int(n/2)+1.
%C A124951 See A285280 for confirmation of linear recurrence and code to produce sequence. - _Ray Chandler_, Aug 12 2023.
%H A124951 Ray Chandler, <a href="/A124951/b124951.txt">Table of n, a(n) for n = 0..99</a>
%H A124951 OEIS Wiki, <a href="/wiki/Number_of_base_k_circular_n-digit_numbers_with_adjacent_digits_differing_by_d_or_less">Number of base k circular n-digit numbers with adjacent digits differing by d or less</a>
%H A124951 <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 A124951 (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 A124951 Cf. Row 23 of A285280.
%K A124951 nonn,base
%O A124951 0,2
%A A124951 _R. H. Hardin_, Dec 28 2006