

A254380


2^2*3^3*...*a(n)^a(n) + 1 is prime, a(n) is prime, a(n)>a(n1), and a(n) is minimal.


0




OFFSET

1,1


COMMENTS



LINKS



EXAMPLE

a(1)=2 because 2 and (2^2)+1=5 are prime.
a(2)=3 because 3 and (2^2*3^3)+1=109 are prime.
a(3)=19 because 19 and (2^2*3^3*19^19)+1=213669322811313867625389733 are prime, and this did not work for either 5, 7, 11, 13.


CROSSREFS



KEYWORD

nonn,hard,more


AUTHOR



EXTENSIONS



STATUS

approved



