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 A267026 #5 Aug 12 2016 06:54:00 %S A267026 720,19,147,1015,15171,255437,4893787,100710495,2166450939 %N A267026 Number of 7Xn arrays containing n copies of 0..7-1 with every element equal to or 1 greater than any northeast or northwest neighbors modulo 7 and the upper left element equal to 0. %C A267026 Row 7 of A267019. %e A267026 Some solutions for n=4 %e A267026 ..0..4..0..3....0..3..0..4....0..3..0..4....0..3..6..3....0..0..0..0 %e A267026 ..4..1..4..1....4..1..4..0....4..1..4..1....4..0..3..6....1..1..1..1 %e A267026 ..1..5..1..5....1..4..1..5....2..5..1..5....0..4..0..3....2..2..2..2 %e A267026 ..5..2..5..2....5..2..5..1....6..2..5..1....4..1..4..1....3..3..3..3 %e A267026 ..2..6..2..6....2..5..2..6....3..6..2..5....1..5..1..5....4..4..4..4 %e A267026 ..6..3..6..3....6..2..6..3....0..3..6..2....6..2..5..2....5..5..5..5 %e A267026 ..3..0..4..0....3..0..3..6....4..0..3..6....2..6..2..5....6..6..6..6 %Y A267026 Cf. A267019. %K A267026 nonn %O A267026 1,1 %A A267026 _R. H. Hardin_, Jan 09 2016