A233113 T(n,k)=Number of nXk 0..5 arrays with no element x(i,j) adjacent to value 5-x(i,j) horizontally or vertically, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order.
1, 2, 2, 6, 19, 6, 23, 313, 313, 23, 99, 6046, 24912, 6046, 99, 452, 123352, 2154065, 2154065, 123352, 452, 2136, 2565169, 189286871, 794723482, 189286871, 2565169, 2136, 10313, 53692063, 16683923848, 294285758398, 294285758398, 16683923848
Offset: 1
Examples
Some solutions for n=3 k=4 ..0..0..0..1....0..0..0..1....0..0..0..1....0..0..0..1....0..0..0..0 ..0..2..2..5....1..1..0..2....1..0..4..2....2..4..2..5....0..0..1..0 ..0..2..1..2....2..1..1..5....0..1..3..1....4..0..0..3....2..2..0..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..180
Formula
Empirical for column k:
k=1: a(n) = 9*a(n-1) -23*a(n-2) +15*a(n-3)
k=2: a(n) = 29*a(n-1) -175*a(n-2) +147*a(n-3)
k=3: a(n) = 111*a(n-1) -2128*a(n-2) +10532*a(n-3) -17559*a(n-4) +9045*a(n-5)
k=4: [order 7]
k=5: [order 15]
Comments