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A056607
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a(n) is the n-th primorial divided by squarefree kernel of corresponding central binomial coefficient.
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0
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2, 3, 10, 35, 231, 3003, 14586, 138567, 5311735, 154040315, 434113615, 16062203755, 354604036745, 15247973580035, 286661903304658, 7596540437573437, 79093391614735197, 4824696888498847017
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OFFSET
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1,1
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LINKS
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FORMULA
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EXAMPLE
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n=6, A002110(6)=30030, C(6,3)=20 with squarefree kernel 10. So a(6) = 30030/10 = 3003 = 3*7*11*13, also squarefree.
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PROG
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(PARI) a(n) = prod(k=1, n, prime(k))/factorback(factor(binomial(n, n\2))[, 1]); \\ Michel Marcus, Jul 13 2018
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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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