%I #10 Aug 21 2021 22:19:12

%S 205,1025,2525,5125,8405,12625,25625,42025,63125,103525,128125,168305,

%T 202525,210125,255025,315625,344605,517625,640625,841525,875125,

%U 1012625,1050625,1275125,1578125,1723025,2042725,2084645

%N Numbers k that divide 4^k + 1, k not a power of 5.

%Y Cf. A015950.

%K nonn

%O 1,1

%A _Robert G. Wilson v_