|
|
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
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
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
|
|
LINKS
|
|
|
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
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|