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A096342
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Primes of the form p*q + p + q, where p and q are two successive primes.
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17
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11, 23, 47, 167, 251, 359, 479, 719, 1847, 2111, 2591, 3719, 6719, 7559, 8819, 10607, 12539, 14591, 19319, 27551, 29231, 31319, 51071, 53819, 68111, 97967, 149759, 155219, 172199, 177239, 195359, 199799, 234239, 273527, 305783, 314711, 339863
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OFFSET
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1,1
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COMMENTS
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a(n) == 3 mod 4.
Number of primes <10^n: 0, 3, 8, 15, 26, 49, 99, 220, 514, 1228, 2991, 7746, 20218, 54081, ..., . - Robert G. Wilson v
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LINKS
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EXAMPLE
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a(4)=167 because 11*13 + 11 + 13=167.
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MATHEMATICA
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a = {}; Do[p = Prime[n]Prime[n + 1] + Prime[n] + Prime[n + 1]; If[ PrimeQ[p], AppendTo[a, p]], {n, 110}]; a (* Robert G. Wilson v, Jul 01 2004 *)
Select[Times@@#+Total[#]&/@Partition[Prime[Range[200]], 2, 1], PrimeQ] (* Harvey P. Dale, Nov 25 2018 *)
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PROG
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(PARI) list(lim)=my(v=List(), p=2, t); forprime(q=3, , t=p*q+p+q; if (t>lim, return(Set(v))); if(isprime(t), listput(v, t)); p=q) \\ Charles R Greathouse IV, Sep 15 2015
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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