A239407 Number of 3Xn 0..3 arrays with no element equal to one plus the sum of elements to its left or two plus the sum of the elements above it, modulo 4.

12, 129, 1337, 13977, 144762, 1504399, 15591122, 161801518, 1677624003, 17403195529, 180479056305, 1871997954119, 19414915574725, 201369918597195, 2088509247416759, 21661501410101827, 224664541142404827

Offset: 1

Author

R. H. Hardin, Mar 17 2014

Keywords

• nonn

Comments

Row 3 of A239405

Examples

			Some solutions for n=4
..3..3..1..3....3..1..0..0....3..3..1..3....0..3..3..0....0..0..3..3
..0..2..1..3....2..2..3..1....2..2..2..2....0..0..0..3....0..0..0..2
..2..0..1..1....0..2..0..1....2..2..3..1....0..2..0..0....3..3..2..2
		

Links

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

Formula

Empirical: a(n) = 8*a(n-1) +73*a(n-2) -446*a(n-3) -1413*a(n-4) +8070*a(n-5) +12185*a(n-6) -63420*a(n-7) -49358*a(n-8) +220534*a(n-9) +39486*a(n-10) -241802*a(n-11) +244780*a(n-12) -89648*a(n-13) -386680*a(n-14) -228008*a(n-15) +129984*a(n-16) -457816*a(n-17) -1064416*a(n-18) -330768*a(n-19) +556128*a(n-20) -351872*a(n-21) +769280*a(n-22) +407552*a(n-23) -200704*a(n-24) +32768*a(n-25)