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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
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.
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
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 28 2016
STATUS
approved