|
%I #7 May 22 2017 10:10:01
%S 6,8,16,27,66,74,168,253,458,1310,2665,2681,2718,2836,4921,7356,11466
%N Numbers n such that primorial(n)/2 - 256 is prime.
%C a(18) > 25000. - _Robert Price_, May 22 2017
%t k = 1; a = {}; Do[k = k*Prime[n]; If[PrimeQ[k - 256]&&k>256, Print[n]; AppendTo[a, n]], {n, 2, 325}]; a
%Y Cf. A067026, A067027, A139439-A139457, A103514.
%K nonn
%O 1,1
%A _Artur Jasinski_, Apr 21 2008
%E Drop 3,4 and correct program, a(9)-a(14) from _Ray Chandler_, Jun 16 2013
%E a(15)-a(17) from _Robert Price_, May 22 2017
|
