A240413 Number of 2Xn 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of the elements above it or zero plus the sum of the elements diagonally to its northwest, modulo 4

5, 10, 32, 80, 162, 493, 1109, 2656, 7235, 16492, 41839, 106203, 251488, 640167, 1579481, 3845121, 9681356, 23735901, 58568055, 145990039, 358605440, 888720845, 2202562818, 5427876319, 13455220186, 33269176662, 82172839773, 203518046217

Offset

1,1

Comments

Row 2 of A240412

Links

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

Formula

Empirical: a(n) = 3*a(n-2) +10*a(n-3) -3*a(n-4) -6*a(n-5) -3*a(n-6) +8*a(n-7) -7*a(n-8) -9*a(n-9) -4*a(n-10) +13*a(n-11) -14*a(n-12) +17*a(n-13) -a(n-15) for n>16

Example

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

Crossrefs

Sequence in context: A221304 A094234 A052538 * A304215 A073705 A355900

Adjacent sequences: A240410 A240411 A240412 * A240414 A240415 A240416

Keyword

nonn

Author

R. H. Hardin, Apr 04 2014

Status

approved