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A103253
Numbers y, without duplication, in Pythagorean triples x,y,z where x,y,z are relatively prime composite numbers and z is a perfect square.
0
7, 28, 41, 63, 112, 119, 161, 164, 175, 239, 252, 343, 369, 448, 476, 527, 567, 644, 656, 700, 721, 847, 956, 959, 1008, 1025, 1071, 1081, 1183, 1241, 1372, 1449, 1476, 1519, 1575, 1792, 1904, 2009, 2023, 2047, 2108, 2268, 2527, 2576, 2624, 2800, 2884, 2975
OFFSET
1,1
COMMENTS
The case where x or y and z are squares does not occur.
LINKS
Chenglong Zou, Peter Otzen, Cino Hilliard, Pythagorean triplets, digest of 6 messages in mathfun Yahoo group, Mar 19, 2005.
EXAMPLE
x=24, y=7, 24^2 + 7^2 = 25^2. 7 is the 1st entry in the list.
PROG
(PARI) pythtrisq(n) = { local(a, b, c=0, k, x, y, z, vy, wx, vx, vz, j); w = vector(n*n+1); for(a=1, n, for(b=1, n, x=2*a*b; y=b^2-a^2; z=b^2+a^2; if(y > 0 & issquare(z), c++; w[c]=y; print(x", "y", "z) ) ) ); vy=vector(c); w=vecsort(w); for(j=1, n*n, if(w[j]>0, k++; vy[k]=w[j]; ) ); for(j=1, 200, print1(vy[j]", ") ) }
CROSSREFS
Sequence in context: A267432 A155712 A015817 * A321777 A269451 A139607
KEYWORD
easy,nonn
AUTHOR
Cino Hilliard, Mar 20 2005
STATUS
approved