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A268421 Number of nX4 0..3 arrays with every repeated value in every row unequal to the previous repeated value, and in every column equal to the previous repeated value, and new values introduced in row-major sequential order.

%I A268421 #4 Feb 04 2016 09:52:21
%S A268421 12,2191,494098,92967597,15615613747,2414369699870,350815694801710,
%T A268421 48579100267639483,6474432977080854160,836528598526349043093,
%U A268421 105356335957177414141417,12989039321265021304747296
%N A268421 Number of nX4 0..3 arrays with every repeated value in every row unequal to the previous repeated value, and in every column equal to the previous repeated value, and new values introduced in row-major sequential order.
%C A268421 Column 4 of A268423.
%H A268421 R. H. Hardin, <a href="/A268421/b268421.txt">Table of n, a(n) for n = 1..43</a>
%e A268421 Some solutions for n=2
%e A268421 ..0..1..0..2....0..0..1..2....0..1..2..2....0..1..0..2....0..0..1..2
%e A268421 ..3..3..1..0....0..2..2..1....1..3..3..1....3..0..0..1....3..0..0..3
%Y A268421 Cf. A268423.
%K A268421 nonn
%O A268421 1,1
%A A268421 _R. H. Hardin_, Feb 04 2016