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A103251 Numbers x, without duplication, in Pythagorean triples x,y,z where x,y,z are relatively prime composite numbers and z is a perfect square. 2
24, 96, 120, 216, 240, 336, 384, 480, 600, 720, 840, 840, 864, 960, 1080, 1176, 1320, 1344, 1536, 1920, 1944, 2016, 2160, 2184, 2400, 2520, 2880, 2904, 3000, 3024, 3360, 3360, 3360, 3456, 3696, 3840, 3960, 4056, 4320, 4704, 4896, 5280, 5280, 5376, 5400 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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

Also area A of the right triangles such that A, the sides and the circumradius are integers. - Michel Lagneau, Mar 15 2012

LINKS

Table of n, a(n) for n=1..45.

MathForFun, Pythagorean triples

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. 24 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]=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: A090214 A283446 A208984 * A256418 A198387 A057102

Adjacent sequences:  A103248 A103249 A103250 * A103252 A103253 A103254

KEYWORD

easy,nonn

AUTHOR

Cino Hilliard, Mar 20 2005

STATUS

approved

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Last modified August 14 05:20 EDT 2022. Contains 356110 sequences. (Running on oeis4.)