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

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

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

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

Adjacent sequences: A240253 A240254 A240255 * A240257 A240258 A240259

Keyword

nonn

Author

R. H. Hardin, Apr 03 2014

Status

approved