A278604 Number of nX1 0..3 arrays with rows and columns in lexicographic nondecreasing order but with exactly three mistakes.

0, 0, 0, 1, 56, 728, 5328, 27876, 116304, 411334, 1281280, 3606980, 9346624, 22597760, 51507280, 111578412, 231211152, 460720740, 886647920, 1653955415, 2999760280, 5303659240, 9161558720, 15492338160, 25689792960, 41836287690

Offset

1,5

Comments

Column 1 of A278610.

Links

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

Formula

Empirical: a(n) = (1/1307674368000)*n^15 + (1/10897286400)*n^14 + (47/9340531200)*n^13 + (17/119750400)*n^12 + (193/93312000)*n^11 + (37/3628800)*n^10 - (26401/457228800)*n^9 - (47183/76204800)*n^8 + (1918993/1306368000)*n^7 + (3793/544320)*n^6 - (386327/25660800)*n^5 - (151381/6652800)*n^4 + (441553891/9081072000)*n^3 + (275711/16816800)*n^2 - (191/5460)*n

Example

Some solutions for n=6
..2. .2. .2. .3. .3. .2. .3. .0. .1. .1. .2. .2. .2. .3. .3. .3
..1. .1. .1. .2. .2. .1. .1. .3. .2. .2. .1. .0. .1. .0. .2. .2
..0. .1. .2. .3. .0. .0. .2. .2. .1. .0. .1. .1. .0. .2. .1. .3
..2. .3. .1. .1. .0. .1. .1. .1. .0. .3. .3. .0. .3. .1. .2. .1
..0. .2. .3. .0. .3. .3. .0. .3. .2. .2. .2. .2. .1. .3. .1. .3
..1. .0. .0. .2. .2. .0. .0. .0. .1. .1. .1. .0. .2. .0. .3. .1

Crossrefs

Cf. A278610.

Sequence in context: A136006 A138410 A240269 * A201098 A190419 A105940

Adjacent sequences: A278601 A278602 A278603 * A278605 A278606 A278607

Keyword

nonn

Author

R. H. Hardin, Nov 23 2016

Status

approved