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%I #8 Sep 10 2017 05:02:37
%S 14,26,34,38,62,74,86,94,118,122,134,142,146,158,194,202,206,214,218,
%T 254,274,278,298,302,314,326,334,362,386,394,398,422,446,454,458,482,
%U 514,526,538,542,554,566,614,622,626,634,662,674,694,698,706,734,746
%N Numbers 2p where p is prime and 2p + 1 is composite.
%e 7 is prime, 2*7 + 1 = 15 is composite, so a(1) = 7*2 = 14.
%p a:=proc(n) if isprime(2*ithprime(n)+1)=false then 2*ithprime(n) else fi end: seq(a(n),n=1..100); # _Emeric Deutsch_, Jul 25 2006
%o (PARI) forprime (p=3,200,if (isprime(2*p+1),print1(2*p",")))
%Y Cf. A005277.
%Y Equals 2 * A053176.
%K nonn,easy
%O 1,1
%A _Jon Perry_, Jan 31 2003
%E More terms from _Emeric Deutsch_, Jul 25 2006
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