Number of distinct solutions of sum{i=1..4}(x(2i-1)*x(2i)) = 1 (mod n), with x() only in 2..n-2.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =5a(5) =13a(6) =103a(7) =302a(8) =1182a(9) =2676a(10) =7472a(11) =14368a(12) =32620a(13) =55157a(14) =110783a(15) =172932a(16) =315241a(17) =457366a(18) =783739a(19) =1088297a(20) =1750273a(21) =2335589a(22) =3624725a(23) =4656872a(24) =6991039a(25) =8758150a(26) =12682152a(27) =15651854a(28) =22182704a(29) =26463796