A074162 a(1) = 1; a(n) = smallest multiple of n (>n) using all nonprime digits (1,4,6,8,9 and 0) if n is a prime else using all prime digits and 1 if n is composite; or 0 if no such number exists.

1, 4, 6, 12, 10, 12, 14, 32, 27, 0, 44, 72, 91, 112, 75, 32, 68, 72, 114, 0, 231, 132, 46, 72, 75, 52, 135, 112, 116, 0, 186, 352, 132, 272, 175, 72, 111, 152, 117, 0, 164, 252, 86, 132, 135, 322, 94, 1152, 735, 0, 153, 312, 106, 1512, 275, 112, 171, 232, 118, 0, 488

Offset

1,2

Comments

a(10k) = 0. Are there other values of n such that a(n) =0?

A pigeonhole argument shows the conjecture to be true (that only a(10k) = 0). - Joshua Zucker, May 08 2006

Conjecture (contradicts Zucker statement): a(k*5^6) = 0. - Sean A. Irvine, Jan 13 2025

Links

Table of n, a(n) for n=1..61.

Crossrefs

Sequence in context: A152678 A110758 A189765 * A365648 A374778 A038040

Adjacent sequences: A074159 A074160 A074161 * A074163 A074164 A074165

Keyword

base,nonn

Author

Amarnath Murthy, Aug 29 2002

Extensions

Corrected and extended by Joshua Zucker, May 08 2006

Status

approved