A278774 Number of nX4 0..1 arrays with rows in nondecreasing lexicographic order and columns in nonincreasing lexicographic order, but with exactly two mistakes.

1, 117, 1972, 19750, 150085, 955347, 5355983, 27218249, 127644118, 559023840, 2305566900, 9009824325, 33520023813, 119176965881, 406212717567, 1330964850429, 4202125841615, 12811256626245, 37790376053439

Offset

1,2

Comments

Column 4 of A278778.

Links

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

R. H. Hardin, Empirical polynomial of degree 36

Formula

Empirical polynomial of degree 36 (see link above)

Example

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

Crossrefs

Cf. A278778.

Sequence in context: A326064 A233376 A233051 * A219990 A223749 A218416

Adjacent sequences: A278771 A278772 A278773 * A278775 A278776 A278777

Keyword

nonn

Author

R. H. Hardin, Nov 28 2016

Status

approved