A240284 T(n,k)=Number of nXk 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 zero plus the sum of the elements diagonally to its northwest, modulo 4.
1, 2, 2, 2, 8, 3, 4, 19, 19, 4, 4, 76, 80, 38, 7, 8, 181, 570, 262, 114, 10, 8, 741, 2574, 3457, 1461, 251, 15, 16, 1779, 20764, 28654, 33183, 5443, 612, 24, 16, 7308, 97348, 443168, 484146, 218658, 24490, 1656, 35, 32, 17561, 802835, 3980245, 13490093, 5646644
Offset: 1
Examples
Some solutions for n=4 k=4 ..3..1..3..3....3..3..1..1....3..1..3..3....3..1..3..1....3..1..3..1 ..3..1..3..2....3..2..1..2....3..1..0..0....3..2..0..1....2..2..2..0 ..3..1..3..2....2..0..2..2....2..2..2..0....3..2..3..2....2..0..0..1 ..2..2..2..0....3..1..0..0....3..1..0..0....2..2..3..3....3..3..0..2
Links
- R. H. Hardin, Table of n, a(n) for n = 1..111
Formula
Empirical for column k:
k=1: a(n) = a(n-2) +2*a(n-3)
k=2: [order 15]
Empirical for row n:
n=1: a(n) = 2*a(n-2)
n=2: a(n) = 12*a(n-2) -24*a(n-4) +31*a(n-6) -16*a(n-8)
n=3: [order 48] for n>51
Comments