OFFSET
1,1
COMMENTS
McDaniel proved that a(n) exists for all n > 0.
Sister sequence of a(n)+n given by A103952.
a(110) > 10^22. - Donovan Johnson, Nov 19 2011
REFERENCES
R. K. Guy, Unsolved Problems in Number Theory, B16
LINKS
Donovan Johnson, Table of n, a(n) for n = 1..109
Wayne L. McDaniel, Representations of every integer as the difference of powerful numbers, Fibonacci Quarterly 20 (1982), pp. 85-87.
Eric Weisstein's World of Mathematics, Powerful numbers
EXAMPLE
214369=463^2 and 214375=5^4*7^3 are the smallest pair of powerful numbers differing by 6, so a(6)=214369.
CROSSREFS
KEYWORD
nonn
AUTHOR
Jud McCranie, Oct 13 2002
EXTENSIONS
More terms from Max Alekseyev, Feb 22 2005
STATUS
approved