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A056607 a(n) is the n-th primorial divided by squarefree kernel of corresponding central binomial coefficient. 0
2, 3, 10, 35, 231, 3003, 14586, 138567, 5311735, 154040315, 434113615, 16062203755, 354604036745, 15247973580035, 286661903304658, 7596540437573437, 79093391614735197, 4824696888498847017 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
FORMULA
a(n) = A002110(n)/A048633(n).
EXAMPLE
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.
PROG
(PARI) a(n) = prod(k=1, n, prime(k))/factorback(factor(binomial(n, n\2))[, 1]); \\ Michel Marcus, Jul 13 2018
CROSSREFS
Sequence in context: A356926 A134959 A270367 * A278051 A060604 A075890
KEYWORD
nonn
AUTHOR
Labos Elemer, Aug 07 2000
STATUS
approved

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Last modified April 20 12:22 EDT 2024. Contains 371842 sequences. (Running on oeis4.)