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 A183883 #7 Jul 22 2025 09:16:37 %S A183883 1,31,1761,75451,1598395,23327655,275846173,2895194179,28388585391, %T A183883 267809160367,2472279047473,22552186971627,204400652073763, %U A183883 1846262280059767,16646854130219781,149959684159252819 %N A183883 Number of arrangements of n+2 numbers in 0..8 with each number being the sum mod 9 of two others. %C A183883 Column 8 of A183884 %H A183883 R. H. Hardin, <a href="/A183883/b183883.txt">Table of n, a(n) for n = 1..53</a> %e A183883 Some solutions for n=2 %e A183883 ..6....3....0....6....0....6....3....3....3....6....3....6....3....3....6....6 %e A183883 ..6....0....0....0....6....3....3....6....3....3....6....3....6....0....0....6 %e A183883 ..3....6....0....3....6....0....6....0....6....0....3....6....6....6....3....3 %e A183883 ..0....3....0....6....3....3....6....3....0....6....0....3....0....6....3....3 %K A183883 nonn %O A183883 1,2 %A A183883 _R. H. Hardin_ Jan 07 2011