Nonnegative k such that 7*k^2 + 7*k + 1 is a square.
A105040
Nonnegative k such that 7*k^2 + 7*k + 1 is a square.
Terms
- a(0) =0a(1) =15a(2) =111a(3) =3936a(4) =28320a(5) =999855a(6) =7193295a(7) =253959360a(8) =1827068736a(9) =64504677711a(10) =464068265775
External references
- oeis: A105040