[go: up one dir, main page]

login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A366399
Triangle read by rows: T(n,k) is the number of paths traveling orthogonally on an n X k grid that visit every cell.
1
1, 1, 4, 1, 8, 20, 1, 14, 62, 276, 1, 22, 132, 1006, 4324, 1, 32, 336, 3610, 26996, 229348, 1, 44, 688, 12010, 109722, 1620034, 13535280, 1, 58, 1578, 38984, 602804, 12071462, 175905310, 3023313284, 1, 74, 3190, 122188, 2434670, 82550864, 1449655468, 43551685370, 745416341496
OFFSET
1,3
EXAMPLE
T(n,k) is a triangular array read by rows:
1,
1, 4,
1, 8, 20,
1, 14, 62, 276,
...
T(2,2) = 4:
+---+---+ +---+---+ +---+---+ +---+---+
| | | | | | | | | | | |
| **|** | | * | * | | **|** | | **|** |
| | * | | * | * | | * | | | * | * |
+---+---+ +---+---+ +---+---+ +---+---+
| | * | | * | * | | * | | | * | * |
| **|** | | **|** | | **|** | | * | * |
| | | | | | | | | | | |
+---+---+ +---+---+ +---+---+ +---+---+
CROSSREFS
See A332307 for another version.
Cf. A120443 (T(n,n)), A366411 (row sums).
Sequence in context: A013611 A297194 A077910 * A100235 A089072 A348595
KEYWORD
tabl,nonn,walk
AUTHOR
Douglas Boffey, Oct 09 2023
EXTENSIONS
More terms (using A332307) from Pontus von Brömssen, Oct 09 2023
STATUS
approved