A267912 Number of 1 X n 0..2 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.

1, 2, 4, 11, 29, 77, 201, 525, 1361, 3525, 9097, 23453, 60353, 155189, 398649, 1023501, 2626289, 6736677, 17274601, 44286845, 113516321, 290925845, 745515417, 1910267373, 4894426193, 12539689989, 32125783369, 82301320541, 210838008449

Offset: 1

Author

R. H. Hardin, Jan 22 2016

Keywords

• nonn

Comments

Row 1 of A267911.

Examples

			Some solutions for n=8:
..0..1..1..2..0..1..2..0....0..1..2..0..2..0..1..0....0..1..2..0..0..1..0..2
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Crossrefs

Cf. A267911.

Formula

Empirical: a(n) = 3*a(n-1) + 2*a(n-2) - 8*a(n-3) for n>5.

Conjectures from Colin Barker, Feb 25 2018: (Start)

G.f.: x*(1 - x - 4*x^2 + 3*x^3 + 4*x^4) / ((1 - 2*x)*(1 - x - 4*x^2)).

a(n) = (1/17)*2^(-5-n)*(-17*4^(1+n) + (85-19*sqrt(17))*(1-sqrt(17))^n + (1+sqrt(17))^n*(85+19*sqrt(17))) for n>2.

(End)