Number of distinct solutions of sum{i=1..7}(x(2i-1)*x(2i)) = 1 (mod n), with x() only in 1..n-1.
A180789
Number of distinct solutions of sum{i=1..7}(x(2i-1)*x(2i)) = 1 (mod n), with x() only in 1..n-1.
Terms
- a(0) =0a(1) =1a(2) =15a(3) =198a(4) =2282a(5) =19300a(6) =126861a(7) =670058a(8) =2997685a(9) =11539243a(10) =39660969a(11) =122371876a(12) =348412793a(13) =914595808a(14) =2264326584a(15) =5259342780a(16) =11692554312a(17) =24683815072a(18) =50403390786a(19) =98560661538a(20) =187881799209a(21) =345060981679a(22) =621482071341
External references
- oeis: A180789