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A125516
Prime numbers that are the sum of three distinct positive squares.
7
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
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
KEYWORD
nonn
AUTHOR
Tomas Xordan, Jan 21 2007
EXTENSIONS
Edited, corrected and extended by Klaus Brockhaus, Feb 11 2007
STATUS
approved