OFFSET
1,2
COMMENTS
If n is prime, then a(n) = p^(n-1) for some prime p (if a(n) exists) as all numbers with n divisors are of this form. - Chai Wah Wu, Dec 04 2014
LINKS
Chai Wah Wu, Table of n, a(n) for n = 1..34
EXAMPLE
The positive integers with exactly 5 divisors are 16 (10000 in binary), 81 (1010001 in binary), etc. 81 is the smallest of these which contains the binary representation of 5 (101) as a substring. (Like this: {101}0001.) So a(5) = 81.
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Leroy Quet, Jun 14 2009
EXTENSIONS
More terms from Sean A. Irvine, Feb 17 2010
More terms from Chai Wah Wu, Dec 04 2014
STATUS
approved