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%I #16 Mar 14 2021 14:26:48
%S 47,72,73,83,98,112,122,123,128,132,133,138,142,148,157,162,172,173,
%T 174,177,183,187,191,192,200,203,208,212,213,216,217,228,233,237,242,
%U 252,253,255,265,268,273,278,288,293,294,302,307,313,317,319
%N Numbers m such that m^2 + 1 can be expressed in more than one way as j^2 + k^2 with j > k > 1 and gcd(j,k) = 1.
%C The sequence differs from A299707 by the gcd condition, which excludes representations like 18^2 + 1 = 15^2 + 10^2, 32^2 + 1 = 25^2 + 20^2, 38^2 + 1 = 34^2 + 17^2.
%H Hugo Pfoertner, <a href="/A300165/b300165.txt">Table of n, a(n) for n = 1..10000</a>
%e a(1) = 47 because its 3 representations satisfy the conditions j > k > 1 and gcd(j,k) = 1: 47^2 + 1 = 2210 = 43^2 + 19^2 = 41^2 + 23^2 = 37^2 + 29^2.
%Y Cf. A050796, A299707, A300166, A300167, A300168.
%K nonn
%O 1,1
%A _Hugo Pfoertner_, Feb 27 2018
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