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A211418
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a(n) = n!*(floor(n/30))!/((floor(n/2))!*(floor(n/3))!*(floor(n/5))!).
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5
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1, 1, 2, 6, 12, 60, 60, 420, 840, 2520, 2520, 27720, 13860, 180180, 360360, 360360, 720720, 12252240, 4084080, 77597520, 38798760, 116396280, 232792560, 5354228880, 1338557220, 6692786100, 13385572200, 40156716600, 80313433200
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OFFSET
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0,3
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COMMENTS
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For positive real r the ratio of factorials floor((30*r*n))! * (floor(r*n))!/((floor(15*r*n))!*(floor(10*r*n))!*(floor(6*r*n))!) is an integer. The present sequence is the case r = 1/30. The case r = 1 is A211417.
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LINKS
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PROG
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(PARI) a(n) = n!*(floor(n/30))!/((floor(n/2))!*(floor(n/3))!*(floor(n/5))!);
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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