OFFSET
1,1
EXAMPLE
a(2)=857: 857 and 859 are twin primes. (857^2+1)^2+1 = 539416802501. 539416802501 and 539416802503 are also twin primes.
CROSSREFS
KEYWORD
nonn
AUTHOR
Ray G. Opao, May 11 2004
STATUS
approved