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A360202
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Array read by antidiagonals: T(m,n) is the number of (non-null) induced trees in the grid graph P_m X P_n.
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7
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1, 3, 3, 6, 12, 6, 10, 33, 33, 10, 15, 78, 138, 78, 15, 21, 171, 533, 533, 171, 21, 28, 360, 2003, 3568, 2003, 360, 28, 36, 741, 7453, 23686, 23686, 7453, 741, 36, 45, 1506, 27643, 156614, 277606, 156614, 27643, 1506, 45, 55, 3039, 102432, 1034875, 3234373, 3234373, 1034875, 102432, 3039, 55
(list;
table;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,2
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LINKS
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Eric Weisstein's World of Mathematics, Grid Graph.
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FORMULA
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T(m,n) = T(n,m).
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EXAMPLE
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Array begins:
=============================================================
m\n| 1 2 3 4 5 6 7 ...
---+---------------------------------------------------------
1 | 1 3 6 10 15 21 28 ...
2 | 3 12 33 78 171 360 741 ...
3 | 6 33 138 533 2003 7453 27643 ...
4 | 10 78 533 3568 23686 156614 1034875 ...
5 | 15 171 2003 23686 277606 3234373 37643572 ...
6 | 21 360 7453 156614 3234373 66136452 1349087217 ...
7 | 28 741 27643 1034875 37643572 1349087217 48136454388 ...
...
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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