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11^n+n^11 is semiprime.
0

%I #9 Sep 08 2022 08:45:23

%S 6,10,16,24,26,48,63

%N 11^n+n^11 is semiprime.

%e 6 is OK because 11^6 + 6^11 = 1771561 + 362797056 = 364568617 = 7*52081231(semiprime).

%o (Magma) IsSemiprime:=func< n | &+[ k[2]: k in Factorization(n) ] eq 2 >; [ n: n in [1..70]|IsSemiprime(11^n+n^11)] // [_Vincenzo Librandi_, Dec 16 2010]

%K nonn

%O 1,1

%A _Zak Seidov_, Feb 22 2006