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Primes of the form abs(2^n - prime(n)^2).
0

%I #12 Jun 01 2014 09:05:39

%S 2,5,17,89,1087,30559,127591,8381719,134207119,140737488310807,

%T 3450873173395281893717377931138512726225554486085193277581262109788439

%N Primes of the form abs(2^n - prime(n)^2).

%C The next term has 138 digits. - _Harvey P. Dale_, Jun 01 2014

%t Union[Select[Table[Abs[2^n-Prime[n]^2],{n,500}],PrimeQ]] (* _Harvey P. Dale_, Jun 01 2014 *)

%o (PARI) print1("2, 5, 17, 89");n=10;forprime(p=31,1e4,if(isprime(t=abs(2^n++-p^2)),print1(", "t))) \\ _Charles R Greathouse IV_, Sep 11 2011

%K nonn

%O 1,1

%A _Juri-Stepan Gerasimov_, Sep 09 2011

%E Terms corrected by _Charles R Greathouse IV_, Sep 11 2011