A278629 Number of nX3 0..2 arrays with rows in nondecreasing lexicographic order and columns in nonincreasing lexicographic order, but with exactly two mistakes.

1, 285, 10824, 234484, 3739008, 48592635, 541463431, 5325263364, 47098291840, 379621129293, 2817194942225, 19407777240447, 124964309624036, 756392815286668, 4325156175914066, 23464134450391209, 121221027131246039

Offset

1,2

Comments

Column 3 of A278634.

Links

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

R. H. Hardin, Empirical polynomial of degree 70

Formula

Empirical polynomial of degree 70 (see link above)

Example

Some solutions for n=3
..1..2..1. .2..0..2. .1..0..2. .2..0..1. .2..0..0. .2..2..1. .0..1..0
..0..0..0. .0..2..0. .0..0..1. .0..2..1. .2..1..2. .2..1..2. .2..2..2
..1..1..0. .2..2..2. .1..0..1. .1..0..2. .2..0..0. .1..2..1. .1..0..0

Crossrefs

Cf. A278634.

Sequence in context: A176712 A225881 A332919 * A241970 A231422 A146893

Adjacent sequences: A278626 A278627 A278628 * A278630 A278631 A278632

Keyword

nonn

Author

R. H. Hardin, Nov 24 2016

Status

approved