A181247 Number of n X 4 binary matrices with no 2 X 2 block having four 1's.

16, 216, 3032, 42176, 587920, 8191392, 114142368, 1590466304, 22161786304, 308805072256, 4302929532288, 59957567962112, 835456401197312, 11641356029819392, 162212139560176128, 2260284639281590272

Offset: 1

Author

R. H. Hardin, Oct 10 2010

Keywords

• nonn

Comments

Column 4 of A181253.

Links

• R. H. Hardin, Table of n, a(n) for n=1..200

Crossrefs

Cf. A181253.

Formula

Empirical: a(n) = 10*a(n-1) + 54*a(n-2) + 16*a(n-3) - 64*a(n-4).

Empirical g.f.: 8*x*(2 + 7*x + x^2 - 8*x^3) / (1 - 10*x - 54*x^2 - 16*x^3 + 64*x^4). - Colin Barker, Mar 26 2018