A051018 Numbers that are 2-persistent but not 3-persistent.

1023456789, 1023456879, 1023457689, 1023457869, 1023458679, 1023458769, 1023465789, 1023465879, 1023467589, 1023467859, 1023468579, 1023468759, 1023475689, 1023475869, 1023476589, 1023476859, 1023478569, 1023478659, 1023485679, 1023485769, 1023486579, 1023486759

Offset: 1

Author

Eric W. Weisstein

Keywords

• nonn
• base

Comments

A number m is k-persistent iff all of {m, 2m,..., km} are pandigital (in the sense of A171102).

Links

• Hans Havermann, Table of n, a(n) for n = 1..1000
• Eric Weisstein's World of Mathematics, Persistent Number

Crossrefs

Cf. A171102 (pandigital), A204047 (smallest n-persistent), A051264 (1-persistent), A051019 (3-persistent), A051020 (4-persistent), A204096 (5-persistent), A204097 (6-persistent).

Programs

PARI

is_A051018(n,k=3)=10>#Set(Vec(Str(k*n))) & !while(k--,9<#Set(Vec(Str(k*n))) || return(0)) \\ M. F. Hasler, Jan 10 2012

Extensions

Definition corrected by Franklin T. Adams-Watters, Jan 09 2012