OFFSET
2,1
COMMENTS
The sequence of largest prime factors of numbers generated by the same sum is probably identical to sequence A006486, since (n^n - 1)/(1 + n^2 + ... + n^(n-1)) = n-1.
LINKS
Chai Wah Wu, Table of n, a(n) for n = 2..178
EXAMPLE
The sum 1 + 4 + 4^2 + 4^3 = 85 = 5 * 17 so the third term is 5.
PROG
(PARI) a(n) = factor(sum(k=0, n-1, n^k))[1, 1]; \\ Michel Marcus, Aug 20 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Axel Harvey, Jan 02 2007
EXTENSIONS
More terms from Michel Marcus, Aug 20 2013
STATUS
approved