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A096342
Primes of the form p*q + p + q, where p and q are two successive primes.
17
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
OFFSET
1,1
COMMENTS
a(n) == 3 mod 4.
Primes arising in A126148. - Jonathan Vos Post, Mar 08 2007
Number of primes <10^n: 0, 3, 8, 15, 26, 49, 99, 220, 514, 1228, 2991, 7746, 20218, 54081, ..., . - Robert G. Wilson v
LINKS
Vincenzo Librandi and Charles R Greathouse IV, Table of n, a(n) for n = 1..10000 (first 1000 terms from Librandi)
EXAMPLE
a(4)=167 because 11*13 + 11 + 13=167.
MATHEMATICA
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 *)
PROG
(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
CROSSREFS
KEYWORD
nonn
AUTHOR
Giovanni Teofilatto, Jun 29 2004
EXTENSIONS
More terms from Robert G. Wilson v, Jul 02 2004
STATUS
approved