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 A200078 #6 Jul 22 2025 15:40:13 %S A200078 1,5,9,17,27,37,85,169,151,219,533,1553,2333,4197,2607,2419,6343, %T A200078 25235,55337,113875,35671 %N A200078 Number of 0..4 arrays x(0..n) of n+1 elements with zero n-1st differences. %C A200078 Column 4 of A200082 %e A200078 Some solutions for n=6 %e A200078 ..3....3....3....4....3....0....1....3....2....2....1....3....1....4....4....4 %e A200078 ..0....3....1....2....2....2....4....2....1....1....0....4....1....3....4....4 %e A200078 ..1....3....1....0....3....4....3....1....0....2....1....3....3....2....2....4 %e A200078 ..3....3....2....0....4....4....1....1....0....3....2....2....4....2....1....4 %e A200078 ..4....3....3....2....4....2....0....2....1....3....2....2....3....3....2....4 %e A200078 ..3....3....3....4....3....0....1....3....2....2....1....3....1....4....4....4 %e A200078 ..0....3....1....2....2....2....4....2....1....1....0....4....1....3....4....4 %K A200078 nonn %O A200078 1,2 %A A200078 _R. H. Hardin_ Nov 13 2011