Number of distinct solutions of sum{i=1..5}(x(2i-1)*x(2i)) = 1 (mod n), with x() only in 2..n-2.
A180828
Number of distinct solutions of sum{i=1..5}(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) =3a(5) =29a(6) =286a(7) =1252a(8) =5910a(9) =18058a(10) =59820a(11) =147057a(12) =385126a(13) =808153a(14) =1819415a(15) =3419890a(16) =6872235a(17) =11853812a(18) =21945574a(19) =35503801a(20) =61441639a(21) =94283546a(22) =155139350a(23) =227922254a(24) =359372638a(25) =509599423a(26) =774249654a(27) =1067712369a(28) =1574987136
External references
- oeis: A180828