Number of non-congruent solutions of x^2+y^2 == z^2+w^2 (mod n).

Terms

a(0) =1a(1) =8a(2) =33a(3) =96a(4) =145a(5) =264a(6) =385a(7) =896a(8) =945a(9) =1160a(10) =1441a(11) =3168a(12) =2353a(13) =3080a(14) =4785a(15) =7680a(16) =5185a(17) =7560a(18) =7201a(19) =13920a(20) =12705a(21) =11528a(22) =12673a(23) =29568a(24) =18625a(25) =18824a(26) =26001a(27) =36960a(28) =25201a(29) =38280