OFFSET
1,1
COMMENTS
2, 6, 30, 210 and 510510 are primorials (A002110). There are no more primorials in the first 300 terms.
Upper bounds for a(14)-a(18): 660393717163700520, 28386773771493397260, 3448055881024876471350, 308480161111936386482910, 32521466098360753728404190.
EXAMPLE
a(7) = 510510 = 714*715 has prime divisors 2, 3, 5, 7, 11, 13 and 17.
CROSSREFS
KEYWORD
hard,nonn
AUTHOR
Amarnath Murthy, Apr 03 2004
EXTENSIONS
Edited, corrected and extended by David Wasserman, Mar 21 2007
a(14)-a(17) from Donovan Johnson, Sep 13 2008
STATUS
approved