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A213426 Irregular array T(n,k) of numbers/2 of non-extendable (complete) non-self-adjacent simple paths of each length within a square lattice bounded by rectangles with nodal dimensions n and 9, n >= 2. 3
4, 4, 6, 10, 14, 20, 30, 44, 60, 60, 28, 2, 4, 8, 16, 22, 54, 70, 152, 238, 416, 574, 810, 642, 760, 456, 320, 136, 72, 8, 4, 8, 20, 40, 84, 126, 268, 418, 1014, 1450, 2890, 3510, 5474, 5286, 7238, 6926, 8218, 5636, 6754, 2956, 4220, 778, 48 (list; graph; refs; listen; history; text; internal format)
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...21...22...23...24...25
.n
.2....4....4....6...10...14...20...30...44...60...60...28....2
.3....4....8...16...22...54...70..152..238..416..574..810..642..760..456..320..136...72....8
.4....4....8...20...40...84..126..268..418.1014.1450.2890.3510.5474.5286.7238.6926.8218.5636.6754.2956.4220..778...48
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 <= 10 are 14, 20, 25, 30, 36, 42, 48, 53. 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 9 node rectangle.
CROSSREFS
Sequence in context: A163976 A213383 A213425 * A054223 A160643 A078321
KEYWORD
nonn,tabf
AUTHOR
STATUS
approved

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Last modified April 23 20:33 EDT 2024. Contains 371916 sequences. (Running on oeis4.)