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A098061 Primes p such that p - 6 is a product of two consecutive primes. 1
41, 83, 149, 227, 443, 673, 1153, 1523, 2027, 4093, 5189, 6563, 7393, 9803, 11027, 12323, 20717, 39209, 47059, 50627, 60497, 64513, 70753, 95483, 104933, 123203, 126733, 131759, 136897, 154439, 181457, 186629, 190093, 194483, 213449, 233279, 251003, 256033 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Is this sequence infinite?
LINKS
EXAMPLE
prime(3)*prime(4) = 35. 35+6 = 41, the first entry in the table.
MATHEMATICA
f[n_]:=Prime[n]*Prime[n+1]+6; lst={}; Do[If[PrimeQ[f[n]], AppendTo[lst, f[n]]], {n, 6!}]; lst (* Vladimir Joseph Stephan Orlovsky, Feb 10 2010 *)
Select[Times@@#+6&/@Partition[Prime[Range[100]], 2, 1], PrimeQ] (* Harvey P. Dale, Apr 25 2011 *)
PROG
(PARI) f(n, m) = for(x=2, n, z=(prime(x+1)*prime(x)); if(isprime(z+m), print1(z+m", ")))
(PARI) is(n)=if(n<9, return(0)); my(q=precprime(sqrtint(n-6))); n-6==q*nextprime(q+1) && isprime(n) \\ Charles R Greathouse IV, Jul 22 2013
CROSSREFS
Sequence in context: A335482 A173550 A136072 * A141898 A054998 A067378
KEYWORD
easy,nonn
AUTHOR
Cino Hilliard, Sep 11 2004
STATUS
approved

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Last modified March 28 05:39 EDT 2024. Contains 371235 sequences. (Running on oeis4.)