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A120681 Sum of legs of primitive Pythagorean triangles sorted first on hypotenuse, then long leg.

%I A120681 #13 Mar 07 2020 07:00:30
%S A120681 7,17,23,31,41,47,49,73,71,89,79,103,113,97,119,137,119,151,127,161,
%T A120681 193,167,161,191,217,239,217,199,257,233,263,223,289,271,311,241,281,
%U A120681 313,329,287,343,287,329,367,391,401,353,431,409,337,383,457,359,463,479
%N A120681 Sum of legs of primitive Pythagorean triangles sorted first on hypotenuse, then long leg.
%C A120681 The prime numbers congruent to +1 or -1 modulo 8 of this sequence appear exactly once. For a proof see the W. Lang link under A001132. - _Wolfdieter Lang_, Feb 17 2015
%H A120681 Ray Chandler, <a href="/A120681/b120681.txt">Table of n, a(n) for n = 1..10000</a>
%F A120681 a(n) = A046087(n) + A046086(n).
%t A120681 A[s_Integer] := With[{s6 = StringPadLeft[ToString[s], 6, "0"]}, Cases[ Import["https://oeis.org/A" <> s6 <> "/b" <> s6 <> ".txt", "Table"], {_, _}][[All, 2]]];
%t A120681 A046086 = A@046086;
%t A120681 A046087 = A@046087;
%t A120681 a[n_] := A046087[[n]] + A046086[[n]];
%t A120681 a /@ Range[10000] (* _Jean-François Alcover_, Mar 07 2020 *)
%Y A120681 Cf. A120682, A058529, A118905, A198390, A001132, A046086, A046087.
%K A120681 nonn
%O A120681 1,1
%A A120681 _Lekraj Beedassy_, Jun 24 2006
%E A120681 Edited and corrected by _Ray Chandler_, Apr 10 2010