A096687 Least k such that decimal representation of k*n contains only digits 0 and 8.

8, 4, 296, 2, 16, 148, 1144, 1, 98765432, 8, 8, 74, 616, 572, 592, 5, 5224, 49382716, 4632, 4, 3848, 4, 38296, 37, 32, 308, 326255144, 286, 303752, 296, 28648, 25, 26936, 2612, 2288, 24691358, 24, 2316, 2072, 2, 2168, 1924, 204856, 2, 197530864, 19148

Offset: 1

Author

Ray Chandler, Jul 12 2004

Keywords

• base
• nonn

Links

• Chai Wah Wu, Table of n, a(n) for n = 1..9998

Crossrefs

Cf. A004290, A078241-A078248, A079339, A096681-A096688.

Programs

Python

def A096687(n):
    if n > 0:
        for i in range(1, 2**n):
            q, r = divmod(8*int(bin(i)[2:]), n)
            if not r:
                return q
    return 1 # Chai Wah Wu, Jan 02 2015

Formula

a(n) = A078247(n)/n.