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%I #7 Oct 20 2014 09:54:19
%S 1,2,15,74,278,541,668,1320,1780,1874,4824,13310,20420,24887
%N Numbers n such that 58/111*(10^(3n)-1)-1 is prime.
%C If n is in the sequence then m=3*(58/111*(10^(3n)-1)-1)) is a term of A072394.
%C Namely if n is a term of this sequence then for m=1/37*(58*10^(3n)-169) we have sigma(m)=reversal(m)-m (see comment lines of A072394).
%C There is no further term up to 3000. Numbers corresponding to the larger terms are probable primes.
%C a(15) > 50000. - _Robert Price_, Oct 20 2014
%t Do[If[PrimeQ[58/111*(10^(3 n) - 1) - 1], Print[n]], {n, 1874}]
%Y Cf. A072394, A178322.
%K more,nonn
%O 1,2
%A _Farideh Firoozbakht_, May 26 2010
%E a(11)-a(14) from _Robert Price_, Oct 20 2014
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