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A240098 Product of the greatest common divisors of n and k! over k=0..n-1. 2
1, 1, 1, 4, 1, 432, 1, 16384, 19683, 800000, 1, 5159780352, 1, 3373232128, 5189853515625, 281474976710656, 1, 499751156776108032, 1, 524288000000000000000, 262757514534242203161, 299170970322599936, 1, 48239864614087244084529856512, 2910383045673370361328125 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,4
LINKS
FORMULA
a(n) = Product_{k=0..n-1} gcd(n,k!) = n^n/A058067(n).
a(p) = 1 for primes p. - Joerg Arndt, Apr 01 2014
a(p^2)= p^(p*(2*p-3)) for primes p. - R. J. Mathar, Apr 02 2014
MAPLE
A240098 := proc(n)
mul( igcd(n, k!), k=0..n-1) ;
end proc:
MATHEMATICA
Table[Times@@Table[GCD[i, n!], {n, 0, i-1}], {i, 30}] (* Harvey P. Dale, Feb 23 2015 *)
PROG
(PARI) a(n) = vecprod(vector(n, k, gcd(n, (k-1)!))); \\ Michel Marcus, Sep 29 2020
CROSSREFS
Cf. A058067.
Sequence in context: A300140 A347554 A298939 * A094337 A345313 A038019
KEYWORD
nonn,easy
AUTHOR
R. J. Mathar, Apr 01 2014
EXTENSIONS
More terms from Harvey P. Dale, Feb 23 2015
a(20) corrected by Amiram Eldar, Sep 29 2020
STATUS
approved

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Last modified July 21 02:16 EDT 2024. Contains 374462 sequences. (Running on oeis4.)