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A164518
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Primes of the form A162143(k) + 2.
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4
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11027, 65027, 74531, 119027, 184043, 308027, 314723, 370883, 423803, 603731, 783227, 804611, 815411, 915851, 938963, 1238771, 1279163, 1461683, 1490843, 1535123, 1550027, 1718723, 2556803, 2673227, 2812331, 3059003, 3493163
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OFFSET
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1,1
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COMMENTS
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Primes of the form 2 + q^2*r^2*s^2 where q, r, and s are three distinct primes.
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LINKS
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EXAMPLE
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MAPLE
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N:= 10^7: # to get all terms <= N
P:= select(isprime, [seq(i, i=3..floor(sqrt(N-2)/15))]):
R:= NULL:
for i from 1 to nops(P) do
for j from 1 to i-1 while (3*P[i]*P[j])^2<=N-2 do
for k from 1 to j-1 do
p:= (P[i]*P[j]*P[k])^2+2;
if p > N then break fi;
if isprime(p) then R:= R, p fi
od od od:
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MATHEMATICA
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f[n_]:=FactorInteger[n][[1, 2]]==2&&Length[FactorInteger[n]]==3&&FactorInteger[n][[2, 2]]==2&&FactorInteger[n][[3, 2]]==2; lst={}; Do[p=Prime[n]; If[f[p-2], AppendTo[lst, p]], {n, 4, 9!}]; lst
With[{nn=30}, Take[Union[Select[Times@@(#^2)+2&/@Subsets[Prime[ Range[ nn]], {3}], PrimeQ]], nn]] (* Harvey P. Dale, Mar 14 2016 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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