A240365 Number of 2Xn 0..3 arrays with no element equal to one plus the sum of elements to its left or two plus the sum of the elements above it or two plus the sum of the elements diagonally to its northwest, modulo 4

4, 15, 51, 188, 672, 2452, 8822, 32077, 115811, 420299, 1519980, 5510943, 19945570, 72279704, 261698918, 948113920, 3433420924, 12437397618, 45043913721, 163158785746, 590931290044, 2140411544446, 7752356423111, 28079348085009

Offset

1,1

Comments

Row 2 of A240364

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +9*a(n-2) -23*a(n-3) -15*a(n-4) +30*a(n-5) +20*a(n-6) +7*a(n-7) -30*a(n-8) +a(n-9) +23*a(n-10) -8*a(n-11) -8*a(n-12)

Example

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

Crossrefs

Sequence in context: A055218 A303843 A107307 * A005492 A003013 A117202

Adjacent sequences: A240362 A240363 A240364 * A240366 A240367 A240368

Keyword

nonn

Author

R. H. Hardin, Apr 04 2014

Status

approved