A064711 - OEIS

%I #18 Sep 08 2022 08:45:04

%S 1,2,4,8,12,14,22,30,36,38,44,50,54,60,66,74,78,84,90,96,106,134,144,

%T 156,162,168,180,188,216,222,224,234,260,264,272,308,324,336,344,366,

%U 368,374,378,390,402,406,422,466,468,476,492,498,502,516,604,624,636

%N Numbers n such that n^2 + prime(n) is a prime.

%H Harry J. Smith, <a href="/A064711/b064711.txt">Table of n, a(n) for n=1..1000</a>

%e 2 is in the sequence because 2^2 + Prime(2) = 4 + 3 = 7 is a prime.

%t Select[ Range[ 1000 ], PrimeQ[ #^2 + Prime[ # ] ] & ]

%o (PARI) { n=0; for (m=1, 10^9, if (isprime(m^2 + prime(m)), write("b064711.txt", n++, " ", m); if (n==1000, break)) ) } \\ _Harry J. Smith_, Sep 23 2009

%o (Magma) [ n: n in [1..700] | IsPrime(n^2+NthPrime(n)) ]; // _Klaus Brockhaus_, Apr 12 2011

%Y Cf. A004232, A184935.

%K easy,nonn

%O 1,2

%A _Robert G. Wilson v_, Oct 13 2001