A096684 Least k such that decimal representation of k*n contains only digits 0 and 5.
5, 25, 185, 125, 1, 925, 715, 625, 61728395, 5, 5, 4625, 385, 3575, 37, 3125, 3265, 308641975, 2895, 25, 2405, 25, 23935, 23125, 2, 1925, 203909465, 17875, 189845, 185, 17905, 15625, 16835, 16325, 143, 1543209875, 15, 14475, 1295, 125, 1355
Offset: 1
Formula
a(n) = A078244(n)/n.