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A103250 Numbers x, without duplication, in Pythagorean triples x,y,z where x,y,z are relatively prime composite numbers and y is a perfect square. 0
30, 40, 120, 130, 160, 270, 272, 312, 350, 360, 480, 510, 520, 640, 738, 750, 888, 1000, 1080, 1088, 1160, 1170, 1200, 1218, 1248, 1342, 1400, 1440, 1470, 1920, 1960, 2040, 2080, 2080, 2210, 2430, 2448, 2560, 2590, 2808, 2952, 2968, 3000, 3150, 3240, 3250 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The case where x and y are both squares cannot occur.

LINKS

Table of n, a(n) for n=1..46.

MathForFun, Title?

EXAMPLE

x=30, y=16, 30^2 + 16^2 = 34^2. 30 is the 1st entry in the list.

PROG

(PARI) pythtrisq(n) = { local(a, b, c=0, k, x, y, z, vy, wx, vx, 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(y), c++; w[c]=x; print(x", "y", "z) ) ) ); vx=vector(c); w=vecsort(w); for(j=1, n*n, if(w[j]>0, k++; vx[k]=w[j]; ) ); for(j=1, 200, print1(vx[j]", ") ) }

CROSSREFS

Sequence in context: A025376 A280640 A152616 * A181638 A166650 A275193

Adjacent sequences:  A103247 A103248 A103249 * A103251 A103252 A103253

KEYWORD

easy,nonn

AUTHOR

Cino Hilliard, Mar 19 2005

STATUS

approved

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Last modified June 16 06:46 EDT 2019. Contains 324145 sequences. (Running on oeis4.)