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A143912
Primes of the form : 2*p+1=p1(prime), 2*p1+3=p2(prime), 2*p2+5=p3(prime).
1
2, 23, 113, 191, 233, 443, 593, 1031, 1409, 2129, 2399, 2543, 4349, 4481, 4919, 5231, 5399, 6263, 6329, 6449, 7541, 10253, 10613, 11321, 12101, 13463, 13553, 13763, 14009, 15773, 15923, 17333, 17939, 18233, 18341, 18461, 18803, 19559, 19661
OFFSET
2,1
COMMENTS
Subset of A005384. [From R. J. Mathar, Sep 05 2008]
LINKS
EXAMPLE
(prime)2*2+1=5(prime), 2*5+3=13(prime), 2*13+5=31(prime).
MATHEMATICA
lst={}; Do[p=Prime[n]; If[PrimeQ[p1=2*p+1]&&PrimeQ[p2=2*p1+3]&&PrimeQ[p3=2*p2+5], AppendTo[lst, p]], {n, 10^4}]; lst
pfQ[n_]:=Module[{p1=2n+1, p2}, p2=2p1+3; And@@PrimeQ[{p1, p2, 2p2+5}]]; Select[Prime[ Range[2300]], pfQ] (* Harvey P. Dale, Nov 03 2011 *)
CROSSREFS
Sequence in context: A201851 A034523 A229222 * A041579 A185830 A301665
KEYWORD
nonn
AUTHOR
STATUS
approved