A328291 a(n) is the greatest k >= 0 such that n*k has distinct decimal digits.

9876543210, 4938271605, 3292181070, 2469135780, 1975308642, 1646090535, 1410934743, 1234567890, 1097393690, 987654321, 897865830, 823045260, 759734010, 705467358, 658436214, 617283945, 580973130, 548696845, 519818058, 493827156, 470311581, 448932915, 429414840

Offset

1,1

Links

David A. Corneth, Table of n, a(n) for n = 1..10000

Rémy Sigrist, PARI program for A328291

Formula

a(n) = A328292(n) / n.

n * a(n) <= 9876543210 for any n > 0.

a(n) = 0 for any n > 9876543210.

a(100*n) = 0 for any n > 0.

a(n) >= 1 for any n in A010784.

1 <= a(n) <= 9 for any n in A050278.

Prog

(PARI) \\ See Links section.
(Python)
from __future__ import division
def A328291(n):
    if n > 9876543210 or n % 100 == 0:
        return 0
    k = 9876543210//n
    m = k*n
    s = str(m)
    while len(set(s)) != len(s):
        k -= 1
        m -= n
        s = str(m)
    return k # Chai Wah Wu, Oct 13 2019

Crossrefs

Cf. A010784, A050278, A328292.

Sequence in context: A027570 A202362 A204058 * A370667 A328292 A154532

Adjacent sequences: A328288 A328289 A328290 * A328292 A328293 A328294

Keyword

nonn,base,easy

Author

Rémy Sigrist, Oct 11 2019.

Extensions

Formula corrected and program amended by Rémy Sigrist, Oct 14 2019

Status

approved