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A240418
Number of nX2 0..3 arrays with no element equal to two 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
7, 35, 147, 553, 2045, 7439, 27099, 98193, 356367, 1290555, 4678201, 16941465, 61383669, 222305205, 805315687, 2916643869, 10564820487, 38264178015, 138597036507, 501986131233, 1818215357263, 6585476407465, 23852672493721
OFFSET
1,1
COMMENTS
Column 2 of A240422
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) +4*a(n-2) -46*a(n-3) +28*a(n-4) +101*a(n-5) -71*a(n-6) -93*a(n-7) -4*a(n-8) +94*a(n-9) +65*a(n-10) -115*a(n-11) -13*a(n-12) +70*a(n-13) -8*a(n-14) -16*a(n-15)
EXAMPLE
Some solutions for n=4
..0..0....0..3....1..1....0..1....0..3....0..0....3..0....0..0....0..3....0..1
..3..3....3..3....0..0....1..1....0..0....0..3....3..3....0..1....3..0....0..1
..0..3....3..3....1..1....1..1....1..0....1..0....3..2....3..0....3..3....1..1
..0..3....1..0....1..1....3..0....1..0....1..0....1..0....3..0....1..2....0..0
CROSSREFS
Sequence in context: A023006 A001875 A169794 * A211843 A121163 A223621
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 04 2014
STATUS
approved