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A054392
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Number of permutations with certain forbidden subsequences.
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2
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1, 1, 2, 5, 14, 42, 131, 418, 1352, 4410, 14463, 47605, 157084, 519255, 1718653, 5693903, 18877509, 62620857, 207816230, 689899944, 2290913666, 7608939443, 25276349558, 83977959853, 279039638062, 927272169336, 3081641953082
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,3
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COMMENTS
| Apparently the Motzkin transform of A005251, after A005251(0) is set to 1. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Dec 11 2008]
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REFERENCES
| E. Barcucci et al., From Motzkin to Catalan Permutations, Discr. Math., 217 (2000), 33-49.
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CROSSREFS
| Interpolates between Motzkin numbers (A001006) and Catalan numbers (A000108). Cf. A005773, A054391-A054394.
Sequence in context: A148328 A080937 A196417 * A006930 A036767 A061922
Adjacent sequences: A054389 A054390 A054391 * A054393 A054394 A054395
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KEYWORD
| nonn
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com), Elisa Pergola (elisa(AT)dsi.unifi.it), May 21 2000
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