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A062080
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Group the even numbers as 2, (4,6), (8,10,12), (14,16,18,20), (22,24,26,28,30), ... then a(n) = LCM of the n-th group.
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1
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2, 12, 120, 5040, 120120, 3255840, 248648400, 3389158080, 893252440080, 147413193127200, 354447322669440, 343973251893070800, 6580115259104106720, 1102084393565113358400, 142057610393676828570720
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OFFSET
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1,1
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LINKS
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EXAMPLE
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a(3) = lcm(8,10,12) = 120.
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PROG
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(PARI) for(n=1, 20, l=1:forstep(s=n^2-n+2, n^2+n, 2, l=lcm(l, s)):print1(l", "))
(PARI) { for (n=1, 100, a=b=n^2 - n + 2; for (k=1, n - 1, a=lcm(a, b + 2*k)); write("b062080.txt", n, " ", a) ) } \\ Harry J. Smith, Jul 31 2009
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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