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A023086 Numbers n such that n and 2*n are anagrams. 14
0, 125874, 128574, 142587, 142857, 258714, 258741, 285714, 285741, 412587, 412857, 425871, 428571, 1025874, 1028574, 1042587, 1042857, 1052874, 1054287, 1072854, 1074285, 1078524, 1078542, 1085274, 1085427, 1087254, 1087425, 1087524, 1087542 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

All terms are divisible by 9. - Eric M. Schmidt, Jul 12 2014

If x and y are in the sequence, then so is 10^k*x + y if y < 10^k. - Robert Israel, Mar 20 2017

LINKS

David W. Wilson, Table of n, a(n) for n = 1..10001

Mark Dominus, When do n and 2n have the same digits?

MAPLE

Res:= 0:

for d from 1 to 7 do

  for n from 10^(d-1)+8 to 5*10^(d-1)-1 by 9 do

    if sort(convert(n, base, 10)) = sort(convert(2*n, base, 10)) then

      Res:= Res, n

    fi

od od:

Res; # Robert Israel, Mar 20 2017

MATHEMATICA

si[n_] := Sort@ IntegerDigits@ n; Flatten@ {0, Table[ Select[ Range[ 10^e+8, 5*10^e-1, 9], si[#] == si[2 #] &], {e, 6}]} (* Giovanni Resta, Mar 20 2017 *)

CROSSREFS

Cf. A023087, A023088, A023089, A023090, A023091, A023092, A023093.

Sequence in context: A252208 A175691 A133220 * A230722 A251016 A251027

Adjacent sequences:  A023083 A023084 A023085 * A023087 A023088 A023089

KEYWORD

nonn,base

AUTHOR

David W. Wilson

STATUS

approved

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Last modified February 18 15:30 EST 2020. Contains 332019 sequences. (Running on oeis4.)