A240418 Number of nX2 0..3 arrays with no element equal to two plus the sum of elements to its left or two plus the sum of elements above it or two plus the sum of the elements diagonally to its northwest, modulo 4

7, 35, 147, 553, 2045, 7439, 27099, 98193, 356367, 1290555, 4678201, 16941465, 61383669, 222305205, 805315687, 2916643869, 10564820487, 38264178015, 138597036507, 501986131233, 1818215357263, 6585476407465, 23852672493721

Offset

1,1

Comments

Column 2 of A240422

Links

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

Formula

Empirical: a(n) = 5*a(n-1) +4*a(n-2) -46*a(n-3) +28*a(n-4) +101*a(n-5) -71*a(n-6) -93*a(n-7) -4*a(n-8) +94*a(n-9) +65*a(n-10) -115*a(n-11) -13*a(n-12) +70*a(n-13) -8*a(n-14) -16*a(n-15)

Example

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

Crossrefs

Sequence in context: A023006 A001875 A169794 * A211843 A121163 A223621

Adjacent sequences: A240415 A240416 A240417 * A240419 A240420 A240421

Keyword

nonn

Author

R. H. Hardin, Apr 04 2014

Status

approved