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A240413
Number of 2Xn 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of the elements above it or zero plus the sum of the elements diagonally to its northwest, modulo 4
1
5, 10, 32, 80, 162, 493, 1109, 2656, 7235, 16492, 41839, 106203, 251488, 640167, 1579481, 3845121, 9681356, 23735901, 58568055, 145990039, 358605440, 888720845, 2202562818, 5427876319, 13455220186, 33269176662, 82172839773, 203518046217
OFFSET
1,1
COMMENTS
Row 2 of A240412
LINKS
FORMULA
Empirical: a(n) = 3*a(n-2) +10*a(n-3) -3*a(n-4) -6*a(n-5) -3*a(n-6) +8*a(n-7) -7*a(n-8) -9*a(n-9) -4*a(n-10) +13*a(n-11) -14*a(n-12) +17*a(n-13) -a(n-15) for n>16
EXAMPLE
Some solutions for n=4
..3..2..3..3....2..3..3..2....3..2..3..2....3..2..2..2....2..3..3..3
..1..0..3..1....2..1..2..0....3..0..1..2....3..0..0..0....2..1..1..2
CROSSREFS
Sequence in context: A221304 A094234 A052538 * A304215 A073705 A355900
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 04 2014
STATUS
approved