A238769 Number of nX2 0..3 arrays with no element equal to the sum modulo 4 of elements to its left or elements above it

6, 30, 156, 810, 4106, 21132, 108124, 553828, 2837376, 14532678, 74442728, 381318484, 1953232394, 10005076766, 51249191766, 262514541710, 1344682852464, 6887891796282, 35281965360630, 180725414294348, 925732869184032

Offset

1,1

Comments

Column 2 of A238775

Links

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

Formula

Empirical: a(n) = a(n-1) +16*a(n-2) +31*a(n-3) -8*a(n-4) -78*a(n-5) -45*a(n-6) +56*a(n-7) -32*a(n-8) +32*a(n-9) +16*a(n-10)

Example

Some solutions for n=5
..1..2....2..1....1..2....2..3....3..2....1..3....1..3....2..3....3..1....3..1
..3..1....1..2....2..3....1..2....1..0....3..0....3..0....3..2....1..3....1..3
..2..0....2..0....2..0....1..3....2..0....3..1....2..1....3..0....1..3....3..1
..1..2....3..0....3..0....2..3....1..3....1..2....1..2....1..2....2..0....1..2
..1..2....3..0....1..2....1..0....2..3....3..0....1..0....3..0....1..0....3..0

Crossrefs

Sequence in context: A127017 A152223 A152224 * A280474 A208790 A026112

Adjacent sequences: A238766 A238767 A238768 * A238770 A238771 A238772

Keyword

nonn

Author

R. H. Hardin, Mar 05 2014

Status

approved