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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.

A203093 Number of n X n 0..3 arrays with every nonzero element less than or equal to some horizontal or vertical neighbor.

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%I A203093 #8 Jul 22 2025 17:01:23
%S A203093 1,84,48552,308642476,27467664499412,32766523337754473494,
%T A203093 516228209623915573866603862,107889416526594162925859037893676244
%N A203093 Number of n X n 0..3 arrays with every nonzero element less than or equal to some horizontal or vertical neighbor.
%C A203093 Diagonal of A203101
%e A203093 Some solutions for n=5
%e A203093 ..1..1..3..3..0....3..3..2..0..2....3..2..3..3..2....0..2..1..0..1
%e A203093 ..3..1..1..3..2....2..0..1..1..2....3..2..2..3..0....0..2..2..1..1
%e A203093 ..3..1..1..0..3....3..1..1..3..1....0..0..3..0..0....3..1..0..1..0
%e A203093 ..2..3..3..0..3....3..3..1..3..0....1..2..3..2..0....3..0..1..2..0
%e A203093 ..2..1..3..2..0....1..2..0..0..0....1..2..0..3..3....3..3..0..2..0
%K A203093 nonn
%O A203093 1,2
%A A203093 _R. H. Hardin_ Dec 29 2011

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