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A240291
Number of nX3 0..3 arrays with no element equal to zero plus the sum of elements to its left or two plus the sum of elements above it or two plus the sum of the elements diagonally to its northwest, modulo 4
1
8, 26, 206, 974, 8064, 38252, 316962, 1502948, 12468758, 59122266, 490548594, 2326075252, 19300603720, 91520046552, 759392572070, 3600913438102, 29878821186710, 141680483207634, 1175603702913842, 5574521174572456
OFFSET
1,1
COMMENTS
Column 3 of A240295
LINKS
FORMULA
Empirical: a(n) = 63*a(n-2) -1109*a(n-4) +7143*a(n-6) -395*a(n-8) -201246*a(n-10) +762860*a(n-12) +347011*a(n-14) -7366154*a(n-16) +11744674*a(n-18) +3758987*a(n-20) +10095295*a(n-22) -126415852*a(n-24) +204390541*a(n-26) -65238786*a(n-28) -59211883*a(n-30) -114625640*a(n-32) +381020006*a(n-34) -342073760*a(n-36) +16725276*a(n-38) +181283664*a(n-40) -110895680*a(n-42) +16492080*a(n-44) +1175136*a(n-46) +390464*a(n-48) for n>50
EXAMPLE
Some solutions for n=4
..3..1..1....1..3..1....3..1..1....3..1..3....1..3..3....3..1..3....3..1..3
..3..2..2....1..0..0....3..2..2....3..0..2....1..2..0....3..0..0....3..2..0
..1..3..2....1..2..2....3..2..0....3..2..2....3..2..2....1..0..3....1..0..2
..3..1..1....3..2..3....1..0..0....1..2..0....1..3..2....3..2..2....3..2..0
CROSSREFS
Sequence in context: A223312 A194997 A089064 * A203635 A000810 A171740
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 03 2014
STATUS
approved