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A164520
Primes p such that p-2 is the product of exactly 2 distinct cubes of primes.
2
274627, 328511, 1860869, 2146691, 2924209, 9129331, 9938377, 10503461, 15438251, 24642173, 26730901, 28372627, 39651823, 61629877, 105823819, 125751503, 136590877, 151419439, 194104541, 426957779, 573856193
OFFSET
1,1
EXAMPLE
274627 - 2 = 5^3*13^3, 328511 - 2 = 3^3*23^3,..
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
PROG
(PARI) forprime(p=3, 1e9, if(ispower(p-2, 3, &n)&&!issquare(n)&&bigomega(n)==2, print1(p", ")))
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
Program by Charles R Greathouse IV, Oct 12 2009
STATUS
approved