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%I #6 Nov 21 2013 12:49:59
%S 1,2,4,8,37,46,50,75,85,106,145,151,163,168,169,207,226,232,260,322,
%T 371,439,449,451,467,522,525,549,573,595,604,656,667,793,832,836,866,
%U 895,923,930,969,1029,1125,1127,1135,1148,1187,1222,1544,1575,1611,1614,1625
%N Numbers n such that 2*prime(n)-1 and 6*prime(n)-1 are prime.
%t pnQ[n_]:=Module[{pn=Prime[n]},And@@PrimeQ[{2pn-1,6pn-1}]]; Select[ Range[ 2000],pnQ] (* _Harvey P. Dale_, Jan 14 2012 *)
%K nonn,easy,less
%O 1,2
%A _Juri-Stepan Gerasimov_, Feb 06 2010
%E Corrected and extended by _Charles R Greathouse IV_, Mar 25 2010