OFFSET
1,1
COMMENTS
Column 3 of A223344
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 18*a(n-1) +585*a(n-2) -5160*a(n-3) -85485*a(n-4) +505600*a(n-5) +3996404*a(n-6) -19237700*a(n-7) -89239938*a(n-8) +375211256*a(n-9) +1104726794*a(n-10) -4232791939*a(n-11) -8081655126*a(n-12) +29153658888*a(n-13) +35808212649*a(n-14) -125320594701*a(n-15) -95870415823*a(n-16) +336725591045*a(n-17) +149825017362*a(n-18) -554412838812*a(n-19) -124734888118*a(n-20) +531808961051*a(n-21) +43836491896*a(n-22) -268190168640*a(n-23) -2736660827*a(n-24) +57764829598*a(n-25) +504580148*a(n-26) -3286957664*a(n-27) +156627216*a(n-28) +43946272*a(n-29) -3289536*a(n-30)
EXAMPLE
Some solutions for n=3
..7..4..3....3..7.12...11.12.11....1..3..4....7.12..7....7.11.12....7..8..5
..3..7..4....7..6..7...10.11..6....2..4..1...12..7..3....8.12.11....6..7..8
..7..4..2...12.11..6...11.12.11....4..2..4....7.12..7....7..8..7....3..6..7
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 19 2013
STATUS
approved