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 A249977 #6 Jun 02 2025 10:16:27 %S A249977 8,42,208,1242,6856,43068,245860,1589346,9213728,60568000,354452340, %T A249977 2354520904,13870730416,92791873776,549357227852,3693928360378, %U A249977 21952690573088,148190103229340,883335481978896,5981390826179620 %N A249977 Number of length n+1 0..2*3 arrays with the sum of the absolute values of adjacent differences equal to n*3. %C A249977 Column 3 of A249982 %H A249977 R. H. Hardin, <a href="/A249977/b249977.txt">Table of n, a(n) for n = 1..210</a> %e A249977 Some solutions for n=6 %e A249977 ..0....3....2....3....6....4....2....6....6....1....0....4....2....0....2....3 %e A249977 ..0....5....5....4....6....1....0....1....0....5....2....0....4....3....6....0 %e A249977 ..3....0....5....6....4....2....4....6....4....3....3....5....3....0....1....0 %e A249977 ..5....3....0....2....0....5....1....6....6....1....6....3....0....1....5....5 %e A249977 ..1....0....5....5....3....6....6....3....2....5....0....0....6....5....4....2 %e A249977 ..5....4....0....0....0....0....6....2....1....2....0....1....5....1....3....5 %e A249977 ..0....5....0....3....6....4....2....6....2....5....6....4....0....4....0....1 %K A249977 nonn %O A249977 1,1 %A A249977 _R. H. Hardin_, Nov 10 2014