Numbers k such that normalizer of Gamma_0(k) is triangle group (2,3,inf).
A018228
Numbers k such that normalizer of Gamma_0(k) is triangle group (2,3,inf).
Terms
- a(0) =1a(1) =4a(2) =9a(3) =16a(4) =36a(5) =64a(6) =144a(7) =576
External references
- oeis: A018228