OFFSET
1,1
COMMENTS
Column 4 of A225900
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..169
FORMULA
Empirical: a(n) = (1/653837184000)*n^16 + (29/186810624000)*n^15 + (71/10059033600)*n^14 + (497/2668723200)*n^13 + (11441/3592512000)*n^12 + (133949/3592512000)*n^11 + (139831/457228800)*n^10 + (227729/130636800)*n^9 + (34734211/4572288000)*n^8 + (43988369/1306368000)*n^7 + (227051569/1437004800)*n^6 + (222061289/718502400)*n^5 + (62570170547/54486432000)*n^4 + (837269/1001000)*n^3 + (36008363/5821200)*n^2 - (302873/180180)*n + 4
EXAMPLE
Some solutions for n=3
..0..0..0..1....0..0..0..1....0..0..1..0....0..0..0..1....0..0..0..0
..1..1..0..0....0..0..0..1....0..0..1..1....0..0..1..1....0..0..1..1
..1..1..1..0....0..1..0..0....0..0..1..1....1..1..0..1....0..1..1..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin May 20 2013
STATUS
approved