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A164521 Primes of the form A162142(k)-2. 0
3373, 753569, 2146687, 3048623, 6539201, 8120599, 10218311, 17373977, 18609623, 19034161, 32461757, 44738873, 59776469, 69426529, 72511711, 77854481, 88121123, 116930167, 133432829, 299418307, 338608871, 413493623, 458314009, 679151437 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Primes p such that p+2 is the cube of a squarefree semiprime, i.e., such that

p+2 = q^3*r^3 where q and r are two distinct primes.

EXAMPLE

3373+2 = 3375 = 3^3*5^3. 753569+1 = 753571 = 7^3*13^3.

MATHEMATICA

f3[n_]:=FactorInteger[n][[1, 2]]==3&&Length[FactorInteger[n]]==2&&FactorInteger[n][[2, 2]]==3; lst={}; Do[p=Prime[n]; If[f3[p+2], AppendTo[lst, p]], {n, 4, 4*9!}]; lst

CROSSREFS

Cf. A006881, A056899, A144953, A164517, A164518, A164519, A164520

Sequence in context: A139779 A117921 A052357 * A183823 A114769 A013803

Adjacent sequences:  A164518 A164519 A164520 * A164522 A164523 A164524

KEYWORD

nonn

AUTHOR

Vladimir Orlovsky (4vladimir(AT)gmail.com), Aug 14 2009

EXTENSIONS

Edited and examples corrected by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Aug 21 2009

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Last modified February 17 13:04 EST 2012. Contains 206022 sequences.