Number of non-congruent solutions to x^2 + y^2 + z^2 + t^2 == 1 (mod n).

Terms

a(0) =1a(1) =8a(2) =24a(3) =64a(4) =120a(5) =192a(6) =336a(7) =512a(8) =648a(9) =960a(10) =1320a(11) =1536a(12) =2184a(13) =2688a(14) =2880a(15) =4096a(16) =4896a(17) =5184a(18) =6840a(19) =7680a(20) =8064a(21) =10560a(22) =12144a(23) =12288a(24) =15000a(25) =17472a(26) =17496a(27) =21504a(28) =24360a(29) =23040