A278408 - OEIS

A278408

Number of nX2 0..2 arrays with rows and columns in lexicographic nondecreasing order but with exactly two mistakes.

0, 20, 264, 2550, 22267, 166762, 1046418, 5586207, 25997719, 107862842, 406276442, 1409360487, 4554092377, 13832291491, 39781304005, 108983918717, 285829839116, 720662237189, 1752986235171, 4126404034476, 9424479791691, 20933182989114

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

COMMENTS

Column 2 of A278414.

LINKS

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

R. H. Hardin, Empirical polynomial of degree 26

FORMULA

Empirical polynomial of degree 26 (see link above)

EXAMPLE

Some solutions for n=4

..2..2. .1..1. .1..0. .0..0. .2..1. .2..0. .0..0. .2..0. .2..0. .2..1

..0..0. .0..1. .2..1. .1..0. .2..2. .0..0. .2..0. .2..1. .2..0. .2..1

..0..0. .1..2. .0..2. .2..1. .0..1. .0..0. .1..2. .0..1. .1..0. .0..2

..1..0. .0..0. .1..0. .1..1. .2..0. .1..1. .1..2. .2..0. .1..0. .2..0

CROSSREFS

Cf. A278414.

Sequence in context: A025943 A025961 A208948 * A229562 A021854 A025939

Adjacent sequences: A278405 A278406 A278407 * A278409 A278410 A278411

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 21 2016

STATUS

approved