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 A074236 Numbers that can be the larger leg of some integer right triangle and hypotenuse of some other integer right triangle. 0
 15, 20, 30, 35, 40, 45, 52, 55, 60, 68, 70, 75, 80, 90, 91, 100, 104, 105, 110, 116, 117, 120, 135, 136, 140, 143, 148, 150, 153, 156, 160, 164, 165, 175, 180, 182, 187, 195, 200, 204, 208, 210, 212, 220, 221, 225, 232, 234, 240, 244, 245, 247, 255, 260, 270 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS A009003 gives ordered values of hypotenuse in i.r.t., A009012 gives ordered values of larger leg in i.r.t.. Intersection of them gives the sequence. Note that all terms are composite. LINKS FORMULA Intersection of A009012 and A009003. EXAMPLE 15 is a member because it is a larger leg in i.r.t. with sides 8, 15, 17 and hypotenuse in i.r.t. with sides 9, 12, 15. MATHEMATICA prims=With[{cps=Select[Subsets[Range[1, 221, 2], {2}], CoprimeQ@@#&]}, ptrip[ {a_, b_}]:={a*b, (b^2-a^2)/2, (b^2+a^2)/2}; Sort[Sort/@(ptrip/@cps)]]; pyths= Sort[Flatten[Table[n #&/@prims, {n, 200}], 1]]; Take[Intersection[ Transpose[ pyths][[2]], Transpose[pyths][[3]]], 80] (* Harvey P. Dale, Apr 26 2012 *) CROSSREFS Cf. A009003, A009012. Sequence in context: A066860 A120159 A163602 * A086770 A111200 A088494 Adjacent sequences:  A074233 A074234 A074235 * A074237 A074238 A074239 KEYWORD nonn AUTHOR Zak Seidov, Sep 18 2002 EXTENSIONS Corrected by Harvey P. Dale, Apr 26 2012 STATUS approved

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Last modified April 18 07:54 EDT 2021. Contains 343084 sequences. (Running on oeis4.)