A125516 Prime numbers that are the sum of three distinct positive squares.

29, 41, 53, 59, 61, 83, 89, 101, 107, 109, 113, 131, 137, 139, 149, 157, 173, 179, 181, 197, 211, 227, 229, 233, 241, 251, 257, 269, 277, 281, 283, 293, 307, 313, 317, 331, 337, 347, 349, 353, 373, 379, 389, 397, 401, 409, 419, 421, 433, 443, 449, 457, 461

Offset

1,1

Links

Zak Seidov, Table of n, a(n) for n = 1..1000

Example

29 = 2^2 + 3^2 + 4^2 = 4 + 9 + 16.
89 = 2^2 + 6^2 + 7^2 = 4 + 36 + 49; also 89 = 3^2 + 4^2 + 8^2 = 9 + 16 + 64.
353 = 2^2 + 5^2 + 18^2 = 4 + 25 + 324; also 353 = 4^2 + 9^2 + 16^2 = 16 + 81 + 256.

Prog

(PARI) {m=22; p=m^2; v=vector(m, x, x^2); w=[]; for(i=1, m-2, for(j=i+1, m-1, for(k=j+1, m, if((n=v[i]+v[j]+v[k])<p&&isprime(n), w=concat(w, n))))); w=listsort(List(w), 1); for(j=1, #w-1, print1(w[j], ", "))} /* Klaus Brockhaus, Feb 11 2007 */

Crossrefs

Cf. A088348, A126657, A126658.

Sequence in context: A155575 A229059 A330653 * A068480 A161616 A069454

Adjacent sequences: A125513 A125514 A125515 * A125517 A125518 A125519

Keyword

nonn

Author

Tomas Xordan, Jan 21 2007

Extensions

Edited, corrected and extended by Klaus Brockhaus, Feb 11 2007

Status

approved