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A291319
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Squarefree triprimes of the form p*q*r such that p+q+r-1 is prime.
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2
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42, 70, 78, 110, 114, 130, 154, 170, 222, 230, 258, 310, 322, 370, 374, 402, 406, 410, 418, 442, 470, 474, 530, 582, 598, 610, 618, 638, 646, 654, 670, 682, 730, 742, 754, 762, 782, 826, 830, 874, 902, 970, 978, 986, 994, 1010, 1030, 1034, 1070, 1158, 1222
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OFFSET
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1,1
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LINKS
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EXAMPLE
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42 = 2*3*7 and 2+3+7-1 is prime, so 42 is a term.
418 = 2*11*19 and 2+11+19-1 is prime, so 418 is a term.
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MATHEMATICA
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With[{nnn=80}, Take[Times@@@Select[Subsets[Prime[Range[nnn]], {3}], PrimeQ[Total[#] - 1] &]//Union, nnn]]
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PROG
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(PARI) list(lim)=my(v=List()); forprime(p=5, lim\6, forprime(q=3, min(lim\2\p, p-2), if(isprime(p+q+1), listput(v, 2*p*q)))); Set(v) \\ Charles R Greathouse IV, Aug 23 2017
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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