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Sequence of 3 Pythagorean triangles, each with a leg and hypotenuse prime. The hypotenuse of each triangle is the leg of the next triangle.
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%I #20 Jun 12 2019 16:28:51

%S 271,349,3001,10099,11719,12281,25889,39901,46399,63659,169219,250361,

%T 264169,287629,289049,312581,353081,440681,473009,502501,502961,

%U 541951,594751,620491,627911,632699,704581,757111,762899,922261,959269

%N Sequence of 3 Pythagorean triangles, each with a leg and hypotenuse prime. The hypotenuse of each triangle is the leg of the next triangle.

%H Ray Chandler, <a href="/A048295/b048295.txt">Table of n, a(n) for n = 1..10000</a>

%H H. Dubner and T. Forbes, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL4/DUBNER/pyth.html">Prime Pythagorean triangles</a>, J. Integer Seqs., Vol. 4 (2001), #01.2.3.

%F For each p(n), q=(p*p+1)/2, r=(q*q+1)/2, s=(r*r+1)/2 and p, q, r, s are all prime.

%e p(5)=271, q=36721, r=674215921, s=227283554064939121.

%Y Cf. A048161, A048270, A308635, A308636. Primes in A188546.

%K nonn

%O 1,1

%A Harvey Dubner (harvey(AT)dubner.com)

%E More terms from _Ray Chandler_, Jun 12 2019