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 A124710 #12 Apr 30 2025 13:58:31
%S A124710 1,17,49,113,301,797,2173,5981,16645,46661,131629,373181,1062481,
%T A124710 3035777,8700601,25002473,72015925,207858677,601040317,1740812621,
%U A124710 5049436441,14666136521,42649909681,124166516801,361855286617
%N A124710 Number of base 17 circular n-digit numbers with adjacent digits differing by 1 or less.
%C A124710 [Empirical] a(base,n)=a(base-1,n)+A002426(n+1) for base>=1.int(n/2)+1
%C A124710 a(n) = T(n, 17) where T(n, k) = Sum_{j=1..k} (1+2*cos(j*Pi/(k+1)))^n. These are the number of smooth cyclic words of length n over the alphabet {1,2,..,17}. See theorem 3.3 in Knopfmacher and others, reference in A124696. - _Peter Luschny_, Aug 13 2012
%H A124710 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>
%o A124710 (S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-1](($[i]`-$[(i+1)mod N]`>1)+($[(i+1)mod N]`-$[i]`>1))
%K A124710 nonn,base
%O A124710 0,2
%A A124710 _R. H. Hardin_, Dec 28 2006