A251067 Number of (3+1)X(n+1) 0..2 arrays with no 2X2 subblock having x11-x00 less than x10-x01

2167, 31895, 320950, 2482824, 15857764, 87634164, 432850109, 1956154249, 8230778879, 32676321575, 123677283286, 449978960436, 1584259322792, 5426858063472, 18167839282369, 59663626761417, 192807960435551

Offset

1,1

Comments

Row 3 of A251065

Links

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

Formula

Empirical: a(n) = 30*a(n-1) -425*a(n-2) +3782*a(n-3) -23721*a(n-4) +111526*a(n-5) -408077*a(n-6) +1190790*a(n-7) -2816743*a(n-8) +5459714*a(n-9) -8729643*a(n-10) +11551618*a(n-11) -12652835*a(n-12) +11438610*a(n-13) -8481295*a(n-14) +5104082*a(n-15) -2453580*a(n-16) +919720*a(n-17) -259024*a(n-18) +51552*a(n-19) -6464*a(n-20) +384*a(n-21)

Example

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

Crossrefs

Sequence in context: A161998 A020421 A203736 * A184558 A097520 A151771

Adjacent sequences: A251064 A251065 A251066 * A251068 A251069 A251070

Keyword

nonn

Author

R. H. Hardin, Nov 29 2014

Status

approved