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A103249 Numbers y, without duplication, in Pythagorean triples x,y,z where x,y,z are relatively prime composite numbers and x is a perfect square. 1
3, 12, 17, 27, 48, 63, 68, 75, 77, 99, 108, 147, 153, 192, 243, 252, 272, 300, 301, 308, 323, 363, 396, 399, 425, 432, 507, 561, 567, 577, 588, 612, 621, 675, 693, 768, 833, 867, 891, 943, 972, 1008, 1023, 1083, 1088, 1200, 1204, 1232, 1292, 1323, 1377, 1377 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

There exists no case in which x and y are both squares.

LINKS

Table of n, a(n) for n=1..52.

MathForFun, Pythagorean triples

EXAMPLE

y=3, x=4, 4^2 + 3^2 = 5^2. 3 is the 1st entry in the list.

PROG

(PARI) pythtrisq(n) = { local(a, b, c=0, k, x, y, z, vy, 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(x), 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: A136047 A082965 A045549 * A047906 A104641 A032703

Adjacent sequences:  A103246 A103247 A103248 * A103250 A103251 A103252

KEYWORD

easy,nonn

AUTHOR

Cino Hilliard, Mar 19 2005

STATUS

approved

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Last modified June 26 04:11 EDT 2019. Contains 324369 sequences. (Running on oeis4.)