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 A124488 Numbers k such that 2*k-1, 4*k-1, 6*k-1, 8*k-1 and 10*k-1 are primes. 2

%I

%S 3,45,6450,18000,22785,41790,54180,77385,87675,98385,103005,104520,

%T 151515,187005,210210,244590,256620,320775,329175,354795,382875,

%U 387975,431385,495540,509355,528510,632775,763815,804870,810540,812175,849285

%N Numbers k such that 2*k-1, 4*k-1, 6*k-1, 8*k-1 and 10*k-1 are primes.

%H Amiram Eldar, <a href="/A124488/b124488.txt">Table of n, a(n) for n = 1..10000</a>

%t Select[Range[900000], And @@ PrimeQ /@ ({2, 4, 6, 8, 10}*# - 1) &] (* _Ray Chandler_, Nov 21 2006 *)

%Y Cf. A124485-A124492.

%K nonn

%O 1,1

%A _Artur Jasinski_, Nov 04 2006

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Last modified December 1 16:44 EST 2021. Contains 349430 sequences. (Running on oeis4.)