A203096 Number of nX3 0..3 arrays with every nonzero element less than or equal to some horizontal or vertical neighbor.

16, 1080, 48552, 2029744, 87531478, 3790420430, 163621176194, 7062389921398, 304924052795176, 13165093367601574, 568388578666214512, 24539653368720439680, 1059478958509288348530, 45742091639005479963848

Offset: 1

Author

R. H. Hardin Dec 29 2011

Keywords

• nonn

Comments

Column 3 of A203101

Examples

			Some solutions for n=5
..1..0..0....2..1..0....1..3..0....0..0..3....1..2..1....1..1..1....0..3..3
..3..2..1....3..3..3....0..3..2....0..1..3....3..2..0....2..2..3....2..3..1
..3..3..3....3..3..2....0..1..2....2..0..2....3..2..2....0..3..3....1..0..3
..3..3..0....1..3..1....0..1..1....2..1..0....0..1..0....0..0..3....2..1..3
..1..1..1....3..3..0....2..3..3....3..3..2....0..1..0....3..3..2....2..3..3
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 50*a(n-1) -535*a(n-2) +11739*a(n-3) -81311*a(n-4) +952118*a(n-5) +111609*a(n-6) [phone]*a(n-7) -3575174*a(n-8) -48024160*a(n-9) -3036762623*a(n-10) -9698998582*a(n-11) -75254884745*a(n-12) -75786404331*a(n-13) [phone]*a(n-14) [phone]*a(n-15) [phone]*a(n-16) [phone]*a(n-17) -35547187154396*a(n-18) -50104627883832*a(n-19) [phone]*a(n-20) [phone]*a(n-21) [phone]*a(n-22) [phone]*a(n-23) -666178095939264*a(n-24) -983552499278784*a(n-25) [phone]*a(n-26) +1440464494146048*a(n-27) -239620376715264*a(n-28) -944613888076800*a(n-29) -83452415201280*a(n-30) [phone]*a(n-31) [phone]*a(n-32) -30045400989696*a(n-33) -8916100448256*a(n-34)