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%I #13 Jun 08 2016 08:06:45
%S 3,5,8,9,12,86,105,147,176,214,230,241,355,412,503,696,1065,1147,1170,
%T 1273,1334,2021,2455,2600,2660,2772,3299,3332,3365,4417,4861,6288,
%U 6478,6572,8115,8858,8905,9229,9380,9590,9692,9749,10501,10829,11338,11633
%N Numbers n such that prime(n) + n is a perfect power.
%e Prime(8) + 8 = 19 + 8 = 27 = 3^3.
%t f[n_] := Prime[n] + n; Select[Range[10^4], ! GCD @@ Last /@ FactorInteger[f[ # ]] == 1 &] (* _Ray Chandler_, May 21 2005 *)
%o (Sage) [n for n in (1..10000) if (n+nth_prime(n)).is_perfect_power()] # _Giuseppe Coppoletta_, Jun 08 2016
%Y Cf. A001597 (perfect powers), A107606 (associated prime(n)+n), A107607, A107608, A109314.
%K nonn
%O 1,1
%A _Zak Seidov_, May 17 2005
%E Extended by _Ray Chandler_, May 21 2005
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