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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.

A201228 Number of n X n 0..3 arrays with every row and column running average nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.

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%I A201228 #8 Jul 22 2025 16:09:55
%S A201228 4,2,114,1028,420662,33222962,112920979339
%N A201228 Number of n X n 0..3 arrays with every row and column running average nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.
%C A201228 Diagonal of A201235
%e A201228 Some solutions for n=4
%e A201228 ..0..0..1..1....0..0..0..1....0..0..0..0....0..0..0..1....0..0..0..0
%e A201228 ..0..2..1..1....0..1..2..1....1..1..2..3....0..1..3..3....1..1..1..2
%e A201228 ..0..3..3..2....2..2..3..3....1..2..3..3....1..2..3..2....1..2..3..2
%e A201228 ..2..2..3..3....1..3..2..3....1..3..2..2....1..2..2..3....2..3..3..3
%K A201228 nonn
%O A201228 1,1
%A A201228 _R. H. Hardin_ Nov 28 2011

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