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A241392
Number of nX2 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of elements above it or zero 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
2, 5, 13, 28, 64, 142, 318, 726, 1634, 3695, 8363, 18904, 42787, 96771, 218940, 495514, 1121224, 2537388, 5742666, 12996786, 29415660, 66576728, 150686121, 341060866, 771951453, 1747237409, 3954724092, 8951198975, 20260385570, 45857968649
OFFSET
1,1
COMMENTS
Column 2 of A241397
LINKS
FORMULA
Empirical: a(n) = 3*a(n-2) +10*a(n-3) +3*a(n-4) -12*a(n-5) -46*a(n-6) -36*a(n-7) +12*a(n-8) +107*a(n-9) +87*a(n-10) +2*a(n-11) -145*a(n-12) -138*a(n-13) -48*a(n-14) +147*a(n-15) +185*a(n-16) +89*a(n-17) -94*a(n-18) -210*a(n-19) -111*a(n-20) +40*a(n-21) +176*a(n-22) +85*a(n-23) +30*a(n-24) -77*a(n-25) -47*a(n-26) -57*a(n-27) +14*a(n-29) +21*a(n-30) +14*a(n-31) -3*a(n-32) +2*a(n-33) -5*a(n-34) +a(n-35) +2*a(n-36) +a(n-37) -a(n-38)
EXAMPLE
Some solutions for n=4
..3..2....2..3....3..2....2..3....2..3....2..3....3..2....2..3....3..2....2..3
..1..0....2..3....1..2....1..3....1..3....1..3....1..0....1..3....1..0....1..3
..2..0....3..0....2..0....2..0....1..0....3..2....3..0....3..2....3..0....3..0
..2..0....2..0....2..3....3..0....2..0....1..2....3..2....2..0....3..0....2..0
CROSSREFS
Sequence in context: A122491 A320933 A290194 * A319778 A354559 A002559
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 20 2014
STATUS
approved