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1000000n+1, 1000000n+3, 1000000n+7, 1000000n+9 are all primes.
0

%I #4 Mar 11 2015 09:11:09

%S 14311,14659,23299,40861,43303,46405,62239,67327,77071,94237,102796,

%T 115201,120220,134968,138721,152980,252715,260947,272365,274534,

%U 285244,298342,304489,305713,311032,318802,324025,325321,338908,343885,352621

%N 1000000n+1, 1000000n+3, 1000000n+7, 1000000n+9 are all primes.

%t Select[Range[10^6/2], PrimeQ[10^6# + 1] && PrimeQ[10^6# + 3] && PrimeQ[10^6# + 7] && PrimeQ[10^6# + 9] &]

%t Select[Range[400000],AllTrue[10^6*#+{1,3,7,9},PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Mar 11 2015 *)

%Y Cf. A007811 and A064687.

%K nonn

%O 1,1

%A _Robert G. Wilson v_, Oct 29 2001