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A158827
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The 4-th iteration of x*C(x) where C(x) is the Catalan function (A000108).
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4
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1, 4, 20, 110, 640, 3870, 24084, 153306, 993978, 6544242, 43652340, 294469974, 2006018748, 13784115468, 95444016984, 665407010349, 4667570034444, 32922870719664, 233389493503968, 1662048903052380, 11885333877149532
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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PROG
| (PARI) {a(n)=local(F=serreverse(x-x^2+O(x^(n+1))), G=x); for(i=1, 4, G=subst(F, x, G)); polcoeff(G, n)}
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CROSSREFS
| Cf. A158825, A158826, A158828, A158829.
Sequence in context: A026127 A153295 A006770 * A026156 A025183 A014523
Adjacent sequences: A158824 A158825 A158826 * A158828 A158829 A158830
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KEYWORD
| nonn
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AUTHOR
| Paul D. Hanna (pauldhanna(AT)juno.com), Mar 28 2009
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