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A080397
Largest squarefree number dividing central binomial coefficient A000984(n).
4
1, 2, 6, 10, 70, 42, 462, 858, 4290, 24310, 92378, 176358, 1352078, 520030, 222870, 6463230, 200360130, 129644790, 907513530, 1767263190, 22974421470, 134564468610, 526024740930, 22870640910, 1074920122770, 1504888171878, 1967930686302, 34766775458002, 1912172650190110
OFFSET
0,2
LINKS
FORMULA
a(n) = A007947(A000984(n)).
MAPLE
a := n -> convert(numtheory:-factorset(binomial(2*n, n)), `*`):
seq(a(n), n=0..25); # Peter Luschny, Oct 31 2015
MATHEMATICA
a[n_] := Times @@ FactorInteger[Binomial[2n, n]][[All, 1]]; Array[a, 26, 0] (* Jean-François Alcover, Jun 04 2019 *)
PROG
(PARI) a(n) = vecprod(factor(binomial(2*n, n))[, 1]); \\ Amiram Eldar, Jun 21 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Mar 19 2003
EXTENSIONS
More terms from Amiram Eldar, Jun 21 2024
STATUS
approved