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A203545
Number of nX3 0..4 arrays with every nonzero element less than or equal to some NW, E or S neighbor
1
1, 430, 32920, 1525965, 67657718, 3251156731, 158110806032, 7562825772263, 360535774171808, 17242013392084148, 825260285534078027, 39475734898738185758, 1887913854619856899927, 90299119197636883779446
OFFSET
1,2
COMMENTS
Column 3 of A203550
LINKS
FORMULA
Empirical: a(n) = 123*a(n-1) -6624*a(n-2) +232336*a(n-3) -6080648*a(n-4) +121676966*a(n-5) -1868615201*a(n-6) +22387963308*a(n-7) -214717844908*a(n-8) +1691861819145*a(n-9) -11191442460825*a(n-10) +63219108066009*a(n-11) -309164051565229*a(n-12) +1321796941127872*a(n-13) -4961324907615666*a(n-14) +16320261542990847*a(n-15) -46804084814900355*a(n-16) +116442440341361329*a(n-17) -250769573867376297*a(n-18) +467917696390546225*a(n-19) -758122812309032702*a(n-20) +1067163197403012168*a(n-21) -1300368495003475068*a(n-22) +1359464763888105924*a(n-23) -1202815292959908360*a(n-24) +885335373771933648*a(n-25) -531402528343591584*a(n-26) +254073967382736576*a(n-27) -93956445379151424*a(n-28) +25800031315475136*a(n-29) -4937126981521536*a(n-30) +586263796939008*a(n-31) -32469600840192*a(n-32) for n>33
EXAMPLE
Some solutions for n=5
..3..4..1....1..3..2....2..4..3....3..0..0....1..4..0....1..2..4....1..2..0
..2..4..2....0..4..3....3..4..3....3..4..2....4..4..4....3..3..4....1..4..3
..3..4..3....4..4..3....3..4..1....3..4..2....0..1..1....0..4..4....4..4..3
..4..4..3....2..4..1....2..4..3....2..4..2....3..2..0....2..4..4....0..4..3
..1..4..3....1..4..4....2..4..4....1..4..4....3..3..0....0..4..4....2..2..3
CROSSREFS
Sequence in context: A166537 A165058 A165062 * A230574 A208627 A176387
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 02 2012
STATUS
approved