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A288518 Array read by antidiagonals: T(m,n) = number of (undirected) paths in the grid graph P_m X P_n. 5
0, 1, 1, 3, 12, 3, 6, 49, 49, 6, 10, 146, 322, 146, 10, 15, 373, 1618, 1618, 373, 15, 21, 872, 7119, 14248, 7119, 872, 21, 28, 1929, 28917, 111030, 111030, 28917, 1929, 28, 36, 4118, 111360, 801756, 1530196, 801756, 111360, 4118, 36 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Paths of length zero are not counted here.

LINKS

Andrew Howroyd, Table of n, a(n) for n = 1..276

Eric Weisstein's World of Mathematics, Graph Path

Eric Weisstein's World of Mathematics, Grid Graph

EXAMPLE

Table starts:

=================================================================

m\n|  1    2      3       4         5          6            7

---|-------------------------------------------------------------

1  |  0    1      3       6        10         15           21 ...

2  |  1   12     49     146       373        872         1929 ...

3  |  3   49    322    1618      7119      28917       111360 ...

4  |  6  146   1618   14248    111030     801756      5493524 ...

5  | 10  373   7119  111030   1530196   19506257    235936139 ...

6  | 15  872  28917  801756  19506257  436619868   9260866349 ...

7  | 21 1929 111360 5493524 235936139 9260866349 343715004510 ...

...

CROSSREFS

Rows 2-3 are A288516, A288527.

Main diagonal is A288032.

Cf. A231829, A064298, A271465, A271592, A120443, A001184, A145157, A003763.

Sequence in context: A162854 A110121 A321710 * A069522 A170857 A227106

Adjacent sequences:  A288515 A288516 A288517 * A288519 A288520 A288521

KEYWORD

nonn,tabl

AUTHOR

Andrew Howroyd, Jun 10 2017

STATUS

approved

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Last modified November 22 10:59 EST 2019. Contains 329389 sequences. (Running on oeis4.)