A206218 Number of (n+1) X 4 0..2 arrays with rows and columns of determinants of all 2 X 2 subblocks lexicographically nondecreasing.

1970, 73133, 1782191, 35625711, 600064928, 9098547899, 131428029860, 1883474084204, 27236695360128, 398320420587108, 5870939348495954, 86941313422965979, 1290991288648976502, 19200795902731377026

Offset

1,1

Comments

Column 3 of A206223.

Links

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

Formula

Empirical: a(n) = 42*a(n-1) -625*a(n-2) +2990*a(n-3) +19429*a(n-4) -300482*a(n-5) +1205989*a(n-6) +739674*a(n-7) -21921768*a(n-8) +68928624*a(n-9) -44135280*a(n-10) -218575584*a(n-11) +570862080*a(n-12) -547928064*a(n-13) +191102976*a(n-14) for n > 30.

Example

Some solutions for n=4
..0..1..0..1....2..0..0..1....2..2..0..1....1..2..1..2....0..0..2..1
..2..0..0..0....2..0..0..1....1..0..0..1....1..1..0..2....2..0..2..1
..1..0..1..1....2..0..0..0....1..0..0..0....1..1..2..2....1..0..1..1
..1..0..2..2....0..0..0..1....1..2..1..0....1..2..1..1....2..0..1..2
..2..2..0..0....0..0..0..2....0..2..2..2....0..2..1..1....1..0..0..1

Crossrefs

Cf. A206223.

Sequence in context: A250804 A205210 A183692 * A255967 A153352 A251816

Adjacent sequences: A206215 A206216 A206217 * A206219 A206220 A206221

Keyword

nonn

Author

R. H. Hardin Feb 04 2012

Status

approved