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Records in the number of ways to express a number of the form n^2 + 1 as j^2 + k^2 with j > k > 1.
5

%I #29 Mar 13 2018 09:09:23

%S 1,2,3,5,7,8,11,15,17,23,31,35,39,47,63,71,95,127,143,161,191,215,255,

%T 287,319,383,575,639,767,959,1151

%N Records in the number of ways to express a number of the form n^2 + 1 as j^2 + k^2 with j > k > 1.

%e a(6) = 8 because A300162(6) = A300161(6)^2 + 1 = 71825 is the smallest number expressible in 8 ways: 71825 = 265^2 + 40^2 = 260^2 + 65^2 = 257^2 + 76^2 = 247^2 + 104^2 = 236^2 + 127^2 = 215^2 + 160^2 = 208^2 + 169^2 = 191^2 + 188^2.

%Y Cf. A060306, A071385, A299707, A299708, A300161, A300162, A300168.

%K nonn,more

%O 1,2

%A _Hugo Pfoertner_, Feb 27 2018

%E a(17) from _Hugo Pfoertner_, Mar 08 2018

%E a(18)-a(21) from _Robert Price_, Mar 10 2018

%E a(22)-a(31) from _Giovanni Resta_, Mar 13 2018