A278623 - OEIS

%I #6 Apr 14 2023 15:37:10

%S 51,1952,49503,1069536,21121532,387542112,6594175430,103536313036,

%T 1496475492375,19928249063688,245280439959902,2802425055340520,

%U 29863427285241827,298206737876251916,2802780797553511873

%N Number of n X 4 0..2 arrays with rows in nondecreasing lexicographic order and columns in nonincreasing lexicographic order, but with exactly one mistake.

%C Column 4 of A278627.

%H R. H. Hardin, <a href="/A278623/b278623.txt">Table of n, a(n) for n = 1..210</a>

%H R. H. Hardin, <a href="/A278623/a278623.txt">Empirical polynomial of degree 125</a>

%F Empirical polynomial of degree 125 (see link above).

%e Some solutions for n=3

%e ..0..2..2..0. .1..1..0..0. .1..1..1..0. .0..0..1..0. .1..1..1..0

%e ..2..0..0..2. .1..1..1..2. .2..1..0..2. .1..1..0..1. .2..0..0..1

%e ..2..2..0..0. .1..1..2..2. .0..1..0..0. .2..1..1..2. .1..0..0..2

%Y Cf. A278627.

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 24 2016