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 A125317 #12 Apr 30 2025 15:00:08 %S A125317 1,7,37,175,925,4977,27067,147777,808165,4422703,24210127,132542813, %T A125317 725664307,3973047319,21752799623,119098967235,652080798837, %U A125317 3570220727531,19547391880633,107024353337437,585971402810715 %N A125317 Number of base 7 circular n-digit numbers with adjacent digits differing by 3 or less. %C A125317 [Empirical] a(base,n)=a(base-1,n)+A025012(n+1) for base>=3.int(n/2)+1. %H A125317 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> %F A125317 G.f.: (1 - 6*x^2 - 28*x^3 + 15*x^4 + 28*x^5 - 5*x^6 - 6*x^7) / ((1 - 2*x - x^2 + x^3)*(1 - 5*x - 3*x^2 + 2*x^3 + x^4)) (conjectured). - _Colin Barker_, Jun 03 2017 %o A125317 (S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-1](($[i]`-$[(i+1)mod N]`>3)+($[(i+1)mod N]`-$[i]`>3)) %K A125317 nonn,base %O A125317 0,2 %A A125317 _R. H. Hardin_, Dec 28 2006