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Zero, together with positive numbers k such that prime(k) - k is a square.
8

%I #35 Apr 16 2024 16:05:47

%S 0,1,2,12,100,118,152,190,212,258,352,462,690,741,1285,1396,1417,2119,

%T 2318,2603,3370,3777,4073,4155,4485,4522,4600,4719,5317,5446,6697,

%U 6748,6985,7144,7595,9492,9551,12010,12985,13438,13850,14672,14739,16510

%N Zero, together with positive numbers k such that prime(k) - k is a square.

%H David A. Corneth, <a href="/A064370/b064370.txt">Table of n, a(n) for n = 1..7110</a> (first 300 terms from Harry J. Smith, terms 301..1000 from Zak Seidov)

%t Join[{0}, Select[Range[50000], IntegerQ[Sqrt[Prime[#] - #]] &]] (* _Paolo Xausa_, Apr 16 2024 *)

%o (PARI) j=[]; for(n=0,20000, if(n==0 || issquare(prime(n)-n), j=concat(j,n))); j

%o (PARI) { n=0; default(primelimit, 20000000); for (m=0, 10^9, if (m==0 || issquare(prime(m) - m), write("b064370.txt", n++, " ", m); if (n==300, break)) ) } \\ _Harry J. Smith_, Sep 13 2009

%o (PARI)

%o upto(n) = {

%o my(t = 0, res = List(0));

%o forprime(p = 2, oo,

%o t++;

%o if(t > n, return(res));

%o if(issquare(p-t),

%o listput(res, t)

%o );

%o );

%o } \\ _David A. Corneth_, Apr 16 2024

%K nonn

%O 1,3

%A _Jason Earls_, Sep 26 2001

%E Edited by _Harry J. Smith_ and _N. J. A. Sloane_, Sep 13 2009