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 A124957 #12 Apr 30 2025 14:53:19
%S A124957 1,29,139,521,2287,10099,45751,209763,971847,4537547,21319129,
%T A124957 100678563,477482659,2272723391,10851284317,51949675591,249291056151,
%U A124957 1198762801227,5775145319281,27868380808227,134681613733997
%N A124957 Number of base 29 circular n-digit numbers with adjacent digits differing by 2 or less.
%C A124957 [Empirical] a(base,n)=a(base-1,n)+A005191(n+1) for base>=2.int(n/2)+1.
%C A124957 See A285280 for confirmation of linear recurrence and code to produce sequence. - _Ray Chandler_, Aug 12 2023.
%H A124957 Ray Chandler, <a href="/A124957/b124957.txt">Table of n, a(n) for n = 0..99</a>
%H A124957 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 A124957 <a href="/index/Rec#order_28">Index entries for linear recurrences with constant coefficients</a>, signature (29, -351, 2223, -7125, 4855, 41169, -116127, -11518, 461660, -394783, -888839, 1297814, 959582, -2082755, -575155, 1998164, 147096, -1203642, 26940, 453526, -29156, -102473, 7707, 12670, -854, -714, 36, 12).
%o A124957 (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 A124957 Cf. Row 29 of A285280.
%K A124957 nonn,base
%O A124957 0,2
%A A124957 _R. H. Hardin_, Dec 28 2006