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Numbers n such that a^r + b^r + c^r + ... is prime, where a*b*c* ... is the prime factorization of n and r is the product of the nonzero digits of n.
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%I #6 Dec 15 2017 17:36:50

%S 10,11,12,14,22,40,54,101,122,136,250,261,300,328,500,539,704,720,850,

%T 1001,1016,1020,1110,1112,1140,1210,1402,2121,2211,2220,2254,2400,

%U 3081,3114,3311,4011,4100,4180,4510,6231,9093,10110,10111,10112,10203,10216

%N Numbers n such that a^r + b^r + c^r + ... is prime, where a*b*c* ... is the prime factorization of n and r is the product of the nonzero digits of n.

%C Of the terms shown, 9093 generates the largest prime, 3^243+7^243+433^243, which has 641 digits. - _David Wasserman_, May 22 2008

%C a(74) = 15273. Of the first 74 terms, a(72) = 14464 generates the largest prime, 7*2^384+113^384, which has 789 digits. - _David Wasserman_, May 22 2008

%e 22 is in the sequence because 22 = 2*11 and 2^(2*2) + 11^(2*2) = 14657, a prime.

%Y Cf. A051801, A082813.

%Y A020449 is a subsequence.

%K base,less,nonn

%O 1,1

%A _Jason Earls_, Jun 19 2005

%E More terms from _David Wasserman_, May 22 2008