A128394 Numbers k such that k^2 divides 14^k - 1.

1, 13, 2041, 24355253, 249302027, 16772956369, 39665616523, 388885239223, 2974921088191, 3487599163841, 61054982558011, 200151688351277, 473329801968959

Offset: 1

Author

Alexander Adamchuk, Mar 01 2007

Keywords

• more
• nonn
• less

Comments

13 divides all except the first term.

Crossrefs

Cf. A127103, A127104, A127105, A127106, A127107, A127102, A127101, A127100, A127092, A128405, A128393, A128395, A128396, A128397, A128398, A128399, A128400, A128401, A128402, A128403, A128404.

Extensions

a(4)-a(5) from Farideh Firoozbakht, Mar 05 2007

a(6)-a(13) from Max Alekseyev, May 06 2010