OFFSET
1,1
COMMENTS
Column 4 of A264059.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 15*a(n-1) -25*a(n-2) +375*a(n-3) -5625*a(n-4) +9375*a(n-5) -15625*a(n-6) +234375*a(n-7) -390625*a(n-8) for n > 10.
EXAMPLE
Some solutions for n=4
..0..8.10.11..4....0..8..2.11.12....0..1.10..3.12....0..1..2..3..4
..5..6..7..1..2....5..6..7..1..9....5.13.15.16..9....5..6..7.16..9
.17..3.19.21.14...10..3..4.21.14....2.18..4..6..7...10.11.20.21.14
.15.16..9.18.12...22.16.24.18.19...22..8.24.11.19...22..8.17.18.19
.20.13.22.23.24...20.13.15.23.17...20.21.14.23.17...12.13.15.23.24
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 02 2015
STATUS
approved