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A240256
Number of nX2 0..3 arrays with no element equal to one plus the sum of elements to its left or one plus the sum of elements above it or one plus the sum of the elements diagonally to its northwest or one plus the sum of the elements antidiagonally to its northeast, modulo 4
1
7, 26, 89, 342, 1362, 5447, 21816, 87527, 351510, 1412417, 5676660, 22817609, 91721666, 368712044, 1482211022, 5958495345, 23953290638, 96293023512, 387101653100, 1556164589581, 6255848045754, 25148780962916, 101099202659613
OFFSET
1,1
COMMENTS
Column 2 of A240260
LINKS
FORMULA
Empirical: a(n) = 8*a(n-1) -20*a(n-2) +16*a(n-3) +4*a(n-4) -25*a(n-5) +53*a(n-6) -68*a(n-7) +100*a(n-8) -62*a(n-9) -41*a(n-10) +34*a(n-11) -117*a(n-12) +108*a(n-13) -54*a(n-14) +93*a(n-15) +41*a(n-16) +20*a(n-17) +8*a(n-18) -41*a(n-19) -26*a(n-20) -41*a(n-21) +9*a(n-22) +5*a(n-23) +2*a(n-24) +4*a(n-25) -13*a(n-26) +4*a(n-27) -3*a(n-28) -2*a(n-29) +4*a(n-30) +a(n-31)
EXAMPLE
Some solutions for n=5
..0..2....2..2....2..0....3..3....0..2....2..0....2..0....2..0....0..2....0..0
..2..2....0..2....0..2....2..2....2..2....0..2....2..2....0..2....0..0....0..2
..2..0....2..0....0..2....0..0....0..2....2..0....2..0....2..0....0..2....0..2
..0..0....0..0....2..0....0..0....0..2....0..2....0..2....0..0....0..2....2..0
..3..3....0..2....0..2....3..3....2..2....0..0....0..0....3..2....2..0....0..2
CROSSREFS
Sequence in context: A335639 A027138 A282703 * A372611 A279761 A245750
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 03 2014
STATUS
approved