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A218581
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Triangle read by rows: T(n,k) is the number of ascent sequences of length n with last occurrence of the maximal value at position k-1.
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5
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1, 0, 2, 0, 1, 4, 0, 1, 4, 10, 0, 1, 6, 15, 31, 0, 1, 10, 29, 62, 115, 0, 1, 18, 63, 148, 288, 496, 0, 1, 34, 149, 392, 826, 1496, 2437, 0, 1, 66, 375, 1120, 2592, 5036, 8615, 13435, 0, 1, 130, 989, 3392, 8698, 18332, 33391, 54548, 82127
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graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,3
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COMMENTS
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LINKS
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EXAMPLE
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Triangle starts:
[ 1] 1,
[ 2] 0, 2,
[ 3] 0, 1, 4,
[ 4] 0, 1, 4, 10,
[ 5] 0, 1, 6, 15, 31,
[ 6] 0, 1, 10, 29, 62, 115,
[ 7] 0, 1, 18, 63, 148, 288, 496,
[ 8] 0, 1, 34, 149, 392, 826, 1496, 2437,
[ 9] 0, 1, 66, 375, 1120, 2592, 5036, 8615, 13435,
[10] 0, 1, 130, 989, 3392, 8698, 18332, 33391, 54548, 82127,
[11] 0, 1, 258, 2703, 10768, 30768, 70868, 138635, 239688, 377001, 551384,
...
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CROSSREFS
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Cf. A022493 (number of ascent sequences).
Cf. A218579 (ascent sequences with last zero at position k-1), A218580 (ascent sequences with first occurrence of the maximal value at position k-1).
Cf. A137251 (ascent sequences with k ascents), A218577 (ascent sequences with maximal element k), A175579 (ascent sequences with k zeros).
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KEYWORD
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AUTHOR
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STATUS
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approved
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