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%I #24 Apr 03 2023 10:36:13
%S 2,3,19,11251
%N 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.
%C Observation: a(2)..a(4) coincide with a(1)..a(3) from A191623. - _Omar E. Pol_, Jan 30 2015
%H Chris K. Caldwell and G. L. Honaker, Jr. <a href="https://t5k.org/curios/page.php?curio_id=27483">Prime Curios!</a>
%e a(1)=2 because 2 and (2^2)+1=5 are prime.
%e a(2)=3 because 3 and (2^2*3^3)+1=109 are prime.
%e 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.
%Y Cf. A000040, A051674, A191623.
%K nonn,hard,more
%O 1,1
%A _G. L. Honaker, Jr._, Jan 29 2015
%E a(4) found by _Chris K. Caldwell_