OFFSET
1,1
COMMENTS
Sum of two positive cubes x^3 + y^3 such that both x+y and x^2 - x*y + y^2 are primes.
The only square is 9. Also, all terms have a unique representation as a sum of two distinct positive cubes. - Zak Seidov, Jun 02 2011
LINKS
Zak Seidov, Table of n, a(n) for n = 1..1356
EXAMPLE
a(2) = 35 because 3^3 + 2^3 = 5*7.
a(5) = 133 = 5^3 + 2^3 = (5+2)*(5^2 - 5*2 + 2^2) = 7*19.
CROSSREFS
KEYWORD
nonn
AUTHOR
Hugo Pfoertner, Jun 25 2003
STATUS
approved