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A084404 Numbers n such that n#*2^n+1 is prime, where n# = product of primes <= n. 0

%I

%S 1,4,7,20,22,27,32,37,48,68,122,128,148,152,155,159,160,198,216,217,

%T 239,247,248,306,363,429,475,515,606,651,823,1491,1774,1923,2153,2469,

%U 2838,2891,2944,3015,3032,3242,3594,4896,5458,5491,5913,6030

%N Numbers n such that n#*2^n+1 is prime, where n# = product of primes <= n.

%C The values 1491 through 6030 have been proved prime; 6030#*2^6030+1 has 4386 decimal digits.

%H OpenPFGW Project, <a href="http://www.primeform.net/openpfgw/">Primality Tester</a>.

%Y Cf. A034386.

%K nonn

%O 1,2

%A _Jason Earls_, Jun 24 2003

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Last modified January 20 01:01 EST 2022. Contains 350467 sequences. (Running on oeis4.)