A267961 - OEIS

%I #6 Jun 17 2021 14:16:03

%S 9,81,576,3969,25281,155236,915849,5253264,29365561,160731684,

%T 863478225,4564353600,23782266225,122339052900,622112365081,

%U 3130733894544,15606442349001,77125175024836,378120197667969,1840241149473024

%N Number of n X 2 0..2 arrays with every repeated value in every row and column greater than the previous repeated value.

%C Column 2 of A267966.

%H R. H. Hardin, <a href="/A267961/b267961.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 21*a(n-1) -153*a(n-2) +263*a(n-3) +2094*a(n-4) -9792*a(n-5) -2752*a(n-6) +86256*a(n-7) -85536*a(n-8) -338048*a(n-9) +554496*a(n-10) +571392*a(n-11) -1335296*a(n-12) -98304*a(n-13) +1179648*a(n-14) -524288*a(n-15).

%e Some solutions for n=6

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

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

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

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

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

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

%Y Cf. A267966.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 22 2016