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A161750
Numbers n such that the decimal digits of 123456789*n are all distinct.
2
0, 1, 2, 4, 5, 7, 8, 10, 11, 13, 14, 16, 17, 20, 22, 23, 25, 26, 31, 32, 34, 35, 40, 41, 43, 44, 50, 52, 53, 61, 62, 70, 71, 80
OFFSET
1,3
LINKS
David Wolfe, When Multiplication Mixes Up Digits, Mathematics Magazine, Volume 80, Number 5, December 2007, pp.380-383
MAPLE
a := proc (n) local nn, nnn: nn := convert(123456789*n, base, 10): nnn := convert(nn, set): if nops(nn) = nops(nnn) then n else end if end proc: seq(a(n), n = 1 .. 80); # Emeric Deutsch, Jun 21 2009
MATHEMATICA
m=123456789; se=Select[Range[0, 99], Sort[id=IntegerDigits[m*# ]]==Union[id]&] (* Zak Seidov, Nov 04 2009 *)
Select[Range[0, 100], Max[DigitCount[123456789#]]==1&] (* Harvey P. Dale, Jun 02 2017 *)
CROSSREFS
Cf. A053654. [From Zak Seidov, Nov 04 2009]
Sequence in context: A003253 A119905 A213219 * A249400 A347782 A226896
KEYWORD
easy,fini,full,nonn,base
AUTHOR
Kyle Stern, Jun 17 2009
EXTENSIONS
a(1)=0 added by Zak Seidov, Nov 04 2009
Edited by Charles R Greathouse IV, Aug 02 2010
STATUS
approved