Numbers k such that 2^(2^k+1) == -1 (mod k^2).

A377026

Numbers k such that 2^(2^k+1) == -1 (mod k^2).

Terms

    a(0) =1a(1) =3a(2) =9a(3) =171a(4) =3249a(5) =97641a(6) =1855179a(7) =29884473a(8) =55753011a(9) =567804987a(10) =892145817a(11) =1059307209

External references