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A205958
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a(0) = 1 and a(n) = A180000(n)*a(floor(n/2))^2 for n > 0.
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2
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1, 1, 1, 1, 2, 2, 3, 3, 48, 16, 40, 40, 270, 270, 945, 63, 129024, 129024, 64512, 64512, 2016000, 96000, 528000, 528000, 144342000, 28868400, 187644600, 20849400, 1787836050, 1787836050, 59594535, 59594535, 3999321544458240, 121191561953280, 1030128276602880
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OFFSET
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0,5
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COMMENTS
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lcm(1,2,..,n) = (n!*a(n)) / ((n/2)!*a(n/2))^2.
lcm(1,2,..,n)*a(n) is a divisor of n! and n!/(lcm(1,2,..,n)*a(n)) is a square.
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LINKS
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PROG
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(Sage)
if n == 0 : return 1
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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