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A064370
Zero, together with positive numbers k such that prime(k) - k is a square.
8
0, 1, 2, 12, 100, 118, 152, 190, 212, 258, 352, 462, 690, 741, 1285, 1396, 1417, 2119, 2318, 2603, 3370, 3777, 4073, 4155, 4485, 4522, 4600, 4719, 5317, 5446, 6697, 6748, 6985, 7144, 7595, 9492, 9551, 12010, 12985, 13438, 13850, 14672, 14739, 16510
OFFSET
1,3
LINKS
David A. Corneth, Table of n, a(n) for n = 1..7110 (first 300 terms from Harry J. Smith, terms 301..1000 from Zak Seidov)
MATHEMATICA
Join[{0}, Select[Range[50000], IntegerQ[Sqrt[Prime[#] - #]] &]] (* Paolo Xausa, Apr 16 2024 *)
PROG
(PARI) j=[]; for(n=0, 20000, if(n==0 || issquare(prime(n)-n), j=concat(j, n))); j
(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
(PARI)
upto(n) = {
my(t = 0, res = List(0));
forprime(p = 2, oo,
t++;
if(t > n, return(res));
if(issquare(p-t),
listput(res, t)
);
);
} \\ David A. Corneth, Apr 16 2024
CROSSREFS
Sequence in context: A012550 A009816 A227084 * A138421 A224403 A219534
KEYWORD
nonn
AUTHOR
Jason Earls, Sep 26 2001
EXTENSIONS
Edited by Harry J. Smith and N. J. A. Sloane, Sep 13 2009
STATUS
approved