A241284 Number of 2Xn 0..3 arrays with no element equal to one plus the sum of elements to its left or zero plus the sum of the 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

4, 3, 5, 13, 17, 35, 90, 141, 288, 670, 1101, 2265, 4995, 8474, 17477, 37329, 64894, 133967, 279966, 496683, 1023868, 2105032, 3799717, 7810452, 15858460, 29052053, 59504463, 119660776, 221989407, 452920894, 904106577, 1695187559, 3445124586

Offset

1,1

Comments

Row 2 of A241283

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = a(n-1) +a(n-2) +7*a(n-3) -8*a(n-4) -7*a(n-5) +9*a(n-7) +10*a(n-8) -24*a(n-9) +5*a(n-10) +29*a(n-11) -18*a(n-12) -10*a(n-13) -10*a(n-14) +16*a(n-15) +12*a(n-16) -12*a(n-17) for n>18

Example

Some solutions for n=4
..3..3..2..3....3..2..3..2....3..3..2..3....3..3..2..3....3..3..2..2
..2..1..1..0....2..1..1..3....2..1..3..0....2..2..3..2....2..1..1..0

Crossrefs

Sequence in context: A277261 A140391 A316965 * A019322 A257301 A298801

Adjacent sequences: A241281 A241282 A241283 * A241285 A241286 A241287

Keyword

nonn

Author

R. H. Hardin, Apr 18 2014

Status

approved