Number of distinct solutions of Sum_{i=1..3}(x(2i-1)*x(2i)) = 0 (mod n), with x() in 0..n-1.

Terms

a(0) =1a(1) =6a(2) =21a(3) =68a(4) =142a(5) =355a(6) =589a(7) =1250a(8) =1946a(9) =3372a(10) =4591a(11) =8432a(12) =10054a(13) =16027a(14) =21564a(15) =31228a(16) =35957a(17) =56543a(18) =61282a(19) =92952a(20) =107265a(21) =139286a(22) =154287a(23) =234348a(24) =238495a(25) =313496a(26) =362400a(27) =469556a(28) =476974a(29) =690961