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Primes of the form colossally abundant number + 1.
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%I #15 Mar 30 2012 18:40:52

%S 3,7,13,61,2521,55441,4324321,367567201,6064949221531201,

%T 9200527969062830401,37188534050951960476801,

%U 8201519488959040182625924708238885435575055666675808001

%N Primes of the form colossally abundant number + 1.

%C The next term is too large to be displayed here.

%C The n-th colossally abundant number + 1 is prime for n = 1, 2, 3, 4, 7, 9, 12, 14, 21, 23, 26, 46, 65, 69, 143, 147.

%F {A004490(i) + 1} INTERSECTION A000040.

%e A004490(12) = 4324320, and 4324320 + 1 = 4324321 is prime.

%e A004490(46) + 1 = 8201519488959040182625924708238885435575055666675808001 is prime.

%Y Cf. A000040, A004490, A136669, A181561, A181562.

%K nonn

%O 1,1

%A _Jonathan Vos Post_, Jan 31 2011