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A166000
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Primes p such that p-5, p-3, p+3, and p+5 are divisible by cubes.
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4
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12253, 14747, 65173, 83003, 93253, 95747, 109139, 147253, 176747, 213349, 255253, 282253, 284747, 287437, 305267, 311747, 315517, 336253, 338747, 364699, 365747, 444253, 452579, 471253, 525253, 554747, 583789, 633253, 716747, 741253, 743747
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OFFSET
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1,1
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COMMENTS
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Contains all primes == 12253 (mod 27000), and therefore the sequence is infinite. - Robert Israel, Apr 21 2016
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LINKS
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MAPLE
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filter:= proc(p) local d;
if not isprime(p) then return false fi;
for d in [-5, -3, 3, 5] do
if max(map(t -> t[2], ifactors(p+d)[2])) < 3 then return false fi;
od;
true
end proc:
select(filter, [seq(t, t=7..10^6, 2)]); # Robert Israel, Apr 21 2016
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MATHEMATICA
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f[n_]:=Max[Last/@FactorInteger[n]]; q=3; lst={}; Do[p=Prime[n]; If[f[p-5]>=q&&f[p-3]>=q&&f[p+3]>=q&&f[p+5]>=q, AppendTo[lst, p]], {n, 4*8!}]; lst
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PROG
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(PARI) ncf(n)={vecmax(factor(n)[, 2])>2}; forprime(p=5, 1e7, if(ncf(p+5)&&ncf(p+3)&&ncf(p-3)&&ncf(p-5), print1(p", "))) /* Charles R Greathouse IV, Oct 05 2009 */
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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