Number of distinct solutions of sum{i=1..4}(x(2i-1)*x(2i)) = 1 (mod n), with x() in 0..n-1.

Terms

a(0) =0a(1) =6a(2) =42a(3) =166a(4) =612a(5) =1649a(6) =4501a(7) =9772a(8) =21631a(9) =39911a(10) =78602a(11) =131634a(12) =234593a(13) =361145a(14) =603810a(15) =883492a(16) =1396448a(17) =1928226a(18) =2949092a(19) =3948312a(20) =5771436a(21) =7496953a(22) =10742472a(23) =13520820a(24) =18931459a(25) =23338564a(26) =31813882a(27) =38799595a(28) =52158316a(29) =61609006