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A154988 Odd numbers that are the right-angle adjacent side in more than one primitive Pythagorean triple with prime hypotenuse 1
15, 35, 39, 45, 51, 65, 69, 85, 95, 105, 141, 145, 159, 165, 175, 195, 205, 209, 221, 231, 245, 255, 261, 275, 279, 285, 299, 309, 315, 325, 329, 345, 371, 375, 391, 399, 415, 425, 435, 455, 459, 465, 471, 519, 535, 545, 555, 559, 561, 575, 581, 585, 595 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..6000

Wikipedia, Pythagorean triple

Eric Rowland, Primitive Integral Solutions to x^2 + y^2 = z^2

EXAMPLE

165 exists in 3 Pythagorean triplets as right-angle adjacent side, (165, 52, 173), (165, 532, 557), (165, 1508, 1517); among these the first two have prime hypotenuse.

MAPLE

filter:= x -> nops(select(t -> subs(t, y)>0 and subs(t, z) > 0 and isprime(subs(t, z)), [isolve(x^2=z^2-y^2)]))>1:

select(filter, [seq(i, i=1..1000, 2)]); # Robert Israel, Aug 30 2016

CROSSREFS

Sequence in context: A134335 A257591 A284406 * A202237 A080774 A146319

Adjacent sequences:  A154985 A154986 A154987 * A154989 A154990 A154991

KEYWORD

nonn

AUTHOR

Avik Roy (avik_3.1416(AT)yahoo.co.in), Jan 18 2009

EXTENSIONS

Data corrected by Robert Israel, Aug 30 2016

STATUS

approved

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Last modified February 23 15:33 EST 2018. Contains 299581 sequences. (Running on oeis4.)