OFFSET
2,1
COMMENTS
The irregular array of numbers is:
...k..3....4....5....6....7....8....9...10...11...12...13...14...15...16...17...18...19...20
.n
.2....4....4....6...10...14...20...26...18....2
.3....4....8...16...22...50...66..132..160..218..120..122...56...36....4
.4....4....8...20...40...80..122..244..336..628..628.1130..788.1362..878.1168..354..292...16
where k is the path length in nodes. There is insufficient evidence to attempt to define the irregularity of the array. However, the maximum values of k for 2 <= n <= 11 are 11, 16, 20, 24, 29, 33, 38, 42, 46, 50. Reading this array by rows gives the sequence. One half of the numbers of paths constitute the sequence to remove the effect of the bilateral symmetry of the rectangle.
LINKS
EXAMPLE
T(2,3) = One half of the number of complete non-self-adjacent simple paths of length 3 nodes within a square lattice bounded by a 2 X 7 node rectangle.
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
Christopher Hunt Gribble, Jun 10 2012
STATUS
approved