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 A134621 Numbers such that the arithmetic mean of the 4th power of their prime factors (taken with multiplicity) is a prime. 15

%I

%S 15,28,39,48,51,65,68,76,77,85,87,93,111,119,133,141,143,148,155,161,

%T 175,187,189,209,212,215,221,225,235,244,275,287,295,301,315,316,320,

%U 323,329,355,393,403,404,411,428,437,447,451,455,481,505,508,515,517

%N Numbers such that the arithmetic mean of the 4th power of their prime factors (taken with multiplicity) is a prime.

%H Hieronymus Fischer, <a href="/A134621/b134621.txt">Table of n, a(n) for n = 1..10000</a>

%e a(3)=39, since 39=3*13 and (3^4+13^4)/2=14321 which is prime.

%Y Cf. A001597, A025475, A134333, A134344, A134376.

%Y Cf. A134600, A134602, A134605, A134608, A134613, A134617, A134619.

%K nonn

%O 1,1

%A _Hieronymus Fischer_, Nov 11 2007

%E Minor edits by _Hieronymus Fischer_, May 06 2013

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