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
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 23 2016
STATUS
approved