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A226754
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Numbers of the form p*q, p and q prime with q=2*p+3.
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2
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14, 65, 119, 377, 629, 779, 1769, 3827, 4559, 5777, 9179, 10877, 16109, 19109, 25877, 32639, 37949, 39059, 49769, 56279, 60377, 75077, 78209, 79799, 100127, 103739, 105569, 145529, 154289, 161027, 189419, 228149, 244649, 250277, 288419, 294527, 316409, 335789
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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fa = FactorInteger; t[n_]:=Length[fa[n]] == 2 && fa[n][[1, 2]]== fa[n][[2, 2]] == 1 && 2 fa[n][[1, 1]]+3 == fa[n][[2, 1]]; Select[1+Range[200000], t]
Times@@#&/@Select[Table[{p, 2p+3}, {p, Prime[Range[200]]}], PrimeQ[#[[2]]]&] (* Harvey P. Dale, Jul 03 2021 *)
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PROG
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(PARI) list(lim)=my(v=List(), q); forprime(p=2, (sqrt(8*lim+9)-3)\4, if(isprime(q=2*p+3), listput(v, p*q))); Vec(v) \\ Charles R Greathouse IV, Nov 19 2013
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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