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A247646
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Irregular triangle read by rows, arising in enumeration of lattice paths in strips.
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1
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1, 1, 3, 3, 1, 1, 3, 9, 5, 7, 11, 1, 3, 9, 15, 12, 10, 9, 3, 1, 1, 1, 3, 9, 15, 27, 16, 20, 12, 14, 3, 3, 1, 1
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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0,3
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COMMENTS
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It would be nice to have a more explicit definition.
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LINKS
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EXAMPLE
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Triangle begins:
1,
1,3,3,1,
1,3,9,5,7,11,
1,3,9,15,12,10,9,3,1,1,
1,3,9,15,27,16,20,12,14,3,3,1,1,
...
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CROSSREFS
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The diagonals on the left are given by A247643.
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KEYWORD
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nonn,tabf,more
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AUTHOR
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STATUS
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approved
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