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A076962
Smallest multiple of prime(n) with n divisors, or 0 if no such number exists.
1
0, 3, 25, 14, 14641, 52, 24137569, 114, 2116, 464, 819628286980801, 444, 22563490300366186081, 2752, 35344, 1272, 21559177407076402401757871041, 2196, 740195513856780056217081017732809, 3408, 341056, 80896, 1658509762573818415340429240403156732495289, 5340
OFFSET
1,2
COMMENTS
If p is a prime then a(p) = prime(p)^(p-1).
No entry is zero for n>1, since prime(n)^(n-1) has exactly n divisors. When n is not prime, this will generally be greater than a(n), but it suffices to prove existence. - Franklin T. Adams-Watters, May 14 2014
PROG
(PARI) a(n) = {if (n==1, return (0)); if (isprime(n), return (prime(n)^(n-1))); np = prime(n); mnp = np; while (numdiv(mnp) != n, mnp += np; ); return (mnp); } \\ Michel Marcus, Mar 19 2013
CROSSREFS
Cf. A076961.
Sequence in context: A224873 A085836 A073916 * A370416 A304480 A129599
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Oct 21 2002
EXTENSIONS
Corrected and extended by Sascha Kurz, Jan 22 2003
More terms from Michel Marcus, Mar 19 2013
STATUS
approved