Numbers k such that k^2 divides 10^k-1.

A127100

Numbers k such that k^2 divides 10^k-1.

Terms

    a(0) =1a(1) =3a(2) =9a(3) =111a(4) =333a(5) =3003003a(6) =111111111a(7) =225121209a(8) =675363627a(9) =27486820443a(10) =32119664517a(11) =82460461329

External references