Number of distinct solutions of sum{i=1..5}(x(2i-1)*x(2i)) = 0 (mod n), with x() only in 2..n-2.

A180817

Number of distinct solutions of sum{i=1..5}(x(2i-1)*x(2i)) = 0 (mod n), with x() only in 2..n-2.

Terms

    a(0) =0a(1) =0a(2) =0a(3) =1a(4) =7a(5) =57a(6) =286a(7) =1701a(8) =5969a(9) =22212a(10) =59824a(11) =173319a(12) =385060a(13) =920819a(14) =1831674a(15) =3839358a(16) =6872225a(17) =13243078a(18) =21945628a(19) =39182616a(20) =61892080a(21) =103355368a(22) =155139308a(23) =251041955a(24) =359562489a(25) =554717344a(26) =780642911a(27) =1160794113a(28) =1574984248

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