A209738 Number of n X 2 0..5 arrays with every 2 X 2 subblock containing exactly one value repeat, and new values 0..5 introduced in row major order.

2, 6, 57, 700, 10594, 183240, 3412100, 65953664, 1298076552, 25767620512, 513555943312, 10254450363264, 204934235829536, 4097247120151424, 81931587030997056, 1638507658307430400, 32769000295781617792

Offset: 1

Author

R. H. Hardin, Mar 12 2012

Keywords

• nonn

Comments

Column 2 of A209744.

Examples

			Some solutions for n=5:
..0..0....0..0....0..0....0..1....0..0....0..0....0..0....0..1....0..1....0..0
..1..2....1..2....1..2....0..2....1..2....1..2....1..2....2..0....1..2....1..2
..0..0....0..0....2..0....0..3....1..0....0..0....2..0....0..3....0..0....1..3
..1..2....3..1....3..0....0..1....0..2....2..3....2..1....2..2....1..2....2..1
..1..3....4..1....0..4....0..2....0..1....2..4....2..0....0..1....1..0....3..1
		

Links

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

Crossrefs

Cf. A209744.

Formula

Empirical: a(n) = 32*a(n-1) - 258*a(n-2) + 296*a(n-3) + 1256*a(n-4) + 480*a(n-5) for n>6.

Empirical g.f.: x*(2 - 58*x + 381*x^2 - 168*x^3 - 1388*x^4 - 536*x^5) / ((1 - 20*x)*(1 - 4*x - 2*x^2)*(1 - 8*x - 12*x^2)). - Colin Barker, Jul 12 2018