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%I #10 Mar 20 2015 19:14:33
%S 9,10,26,33,65,82,122,129,145,217,226,362,485,626,785,842,901,1157,
%T 1226,1522,1765,1937,2026,2049,2117,2305,2402,2501,2602,2705,3365,
%U 3482,3601,3722,3845,4097,4226,4762,5042,5777,5833,6085,6242,6401,7226,7397,7745,8193,8465,9026,9217
%N Semiprimes which are one more than a perfect power.
%C Numbers of the form p*q where p and q are primes, not necessarily distinct, such that p*q - 1 is a perfect power (squares, cubes, etcetera). _T. D. Noe_ suggested the name semiprimes which are super-perfect powers.
%C The number of terms <= 10^k: 2, 6, 17, 51, 131, 379, 1015, 2865, 8086, ..., . - _Robert G. Wilson v_, Apr 16 2011
%H Robert G. Wilson v, <a href="/A189047/b189047.txt">Table of n, a(n) for n = 1..8086</a>
%F A001358 INTERSECTION {A001597 + 1}.
%e a(21) = 42^2 + 1 = 1765 = 5 * 353.
%t fQ[n_] := GCD @@ Last /@ FactorInteger[n - 1] > 1 && Plus @@ Last /@ FactorInteger[n] == 2; Select[ Range@ 10000, fQ] (* _Robert G. Wilson v_, Apr 16 2011 *)
%Y Cf. A001358, A001597, A045542, A177955, A189045.
%K easy,nonn
%O 1,1
%A _Jonathan Vos Post_, Apr 15 2011
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