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A152388
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Primes p such that (p-n)/(n+1) and (n+1)*p+n are both prime, with n=127.
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1
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6143, 11519, 23039, 205823, 253439, 345599, 417023, 463103, 752639, 1071359, 1474559, 1511423, 1753343, 1766399, 1903103, 2188799, 2271743, 2711039, 2741759, 2747903, 2813183, 2997503, 3032063, 3258623, 3371519, 3463679
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OFFSET
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1,1
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COMMENTS
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This is the general form : (p-n)/(n+1)=primeand(n+1)*p+n=prime; 'Safe' primes and'Sophie Germain' primes just one part of this general form; If n=1 then we got'Safe' primes and'Sophie Germain' primes.
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LINKS
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MATHEMATICA
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lst={}; n=127; Do[p=Prime[k]; If[PrimeQ[(p-n)/(n+1)]&&PrimeQ[(n+1)*p+n], AppendTo[lst, p]], {k, 2*9!}]; lst
Select[Prime[Range[250000]], AllTrue[{(#-127)/128, 128#+127}, PrimeQ]&] (* Harvey P. Dale, Apr 30 2023 *)
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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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