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Numbers of the form m^2 + 1 that can be expressed in more than one way as j^2 + k^2 with j > k > 1 and gcd(j,k) = 1.
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%I #16 Mar 14 2021 18:45:00

%S 2210,5185,5330,6890,9605,12545,14885,15130,16385,17425,17690,19045,

%T 20165,21905,24650,26245,29585,29930,30277,31330,33490,34970,36482,

%U 36865,40001,41210,43265,44945,45370,46657,47090,51985,54290,56170,58565,63505

%N Numbers of the form m^2 + 1 that 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 A299708 by the gcd condition, which excludes representations like 325 = 18^2 + 1^2 = 15^2 + 10^2, 1025 = 32^2 + 1 = 25^2 + 20^2, 1445 = 38^2 + 1 = 34^2 + 17^2.

%H Hugo Pfoertner, <a href="/A300166/b300166.txt">Table of n, a(n) for n = 1..10000</a>

%e a(1) = 2210 because its 3 representations satisfy the conditions j > k > 1 and gcd(j,k) = 1: 2210 = 47^2 + 1 = 43^2 + 19^2 = 41^2 + 23^2 = 37^2 + 29^2.

%Y Cf. A050796, A299707, A299708, A300165, A300167, A300168.

%K nonn

%O 1,1

%A _Hugo Pfoertner_, Feb 27 2018