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A254380
2^2*3^3*...*a(n)^a(n) + 1 is prime, a(n) is prime, a(n)>a(n-1), and a(n) is minimal.
0
2, 3, 19, 11251
OFFSET
1,1
COMMENTS
Observation: a(2)..a(4) coincide with a(1)..a(3) from A191623. - Omar E. Pol, Jan 30 2015
LINKS
Chris K. Caldwell and G. L. Honaker, Jr. Prime Curios!
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
G. L. Honaker, Jr., Jan 29 2015
EXTENSIONS
a(4) found by Chris K. Caldwell
STATUS
approved