login
A181247
Number of n X 4 binary matrices with no 2 X 2 block having four 1's.
1
16, 216, 3032, 42176, 587920, 8191392, 114142368, 1590466304, 22161786304, 308805072256, 4302929532288, 59957567962112, 835456401197312, 11641356029819392, 162212139560176128, 2260284639281590272
OFFSET
1,1
COMMENTS
Column 4 of A181253.
LINKS
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
CROSSREFS
Cf. A181253.
Sequence in context: A269290 A297098 A159739 * A138454 A235758 A086650
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 10 2010
STATUS
approved