A278548 Number of nX2 0..3 arrays with rows and columns in lexicographic nondecreasing order but with exactly two mistakes.

0, 70, 1531, 25402, 385040, 4880813, 50476458, 435272199, 3222371162, 21002624643, 122940347621, 656384657007, 3235421775340, 14866063786408, 64169850484506, 261881056692205, 1015819011059751, 3761887253493383

Offset

1,2

Comments

Column 2 of A278553.

Links

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

R. H. Hardin, Empirical polynomial of degree 47

Formula

Empirical polynomial of degree 47 (see link above)

Example

Some solutions for n=4
..3..0. .3..0. .0..0. .0..1. .1..3. .1..3. .2..3. .2..1. .1..1. .2..2
..3..2. .2..2. .2..2. .2..3. .3..3. .1..1. .3..1. .2..2. .2..1. .3..2
..1..0. .3..1. .3..2. .2..1. .2..3. .3..3. .3..0. .2..3. .0..0. .0..3
..1..2. .3..2. .2..2. .1..3. .0..2. .2..2. .1..3. .2..1. .2..3. .1..2

Crossrefs

Cf. A278553.

Sequence in context: A061606 A331351 A298973 * A107421 A076430 A006296

Adjacent sequences: A278545 A278546 A278547 * A278549 A278550 A278551

Keyword

nonn

Author

R. H. Hardin, Nov 23 2016

Status

approved