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Primes p such that all prime factors of p-2 have exponent 3.
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%I #21 Jan 14 2025 15:25:44

%S 3,29,127,24391,274627,328511,357913,571789,1157627,1442899,1860869,

%T 2146691,2924209,5177719,9129331,9938377,10503461,12326393,15438251,

%U 18191449,24642173,26730901,28372627,30080233,39651823

%N Primes p such that all prime factors of p-2 have exponent 3.

%C A048636 is the subsequence of terms where there is only one prime divisor of p-2. - _M. F. Hasler_, Jan 13 2025

%H Charles R Greathouse IV, <a href="/A188764/b188764.txt">Table of n, a(n) for n = 1..10000</a>

%H Charles R Greathouse IV, <a href="/A188764/b188764_1.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) >> n^3. - _Charles R Greathouse IV_, Jan 14 2025

%e 30080233-2=311^3, 39651823-2=11^3*31^3,...

%e 3-2 = 1 has no prime factors, so is trivially a member.

%t Select[Table[Prime[n],{n,3000000}],Length[Union[Last/@FactorInteger[#-2]]]==1&&Union[Last/@FactorInteger[#-2]]=={3}&]

%t Select[Prime[Range[25*10^5]],Union[FactorInteger[#-2][[All,2]]]=={3}&] (* _Harvey P. Dale_, Nov 22 2018 *)

%o (PARI) list(lim)=my(v=List()); forsquarefree(k=1,sqrtnint(lim\1-2,3), my(p=k[1]^3+2); if(isprime(p), listput(v,p))); Vec(v) \\ _Charles R Greathouse IV_, Jan 14 2025

%Y Subsequence of A144953; A048636 is a subsequence.

%Y Cf. A089195, A188717.

%K nonn,changed

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Apr 09 2011