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A292125 Positive numbers n such that the set of base-7 digits of n equals both the set of base-8 digits of n and the set of base-9 digits of n. 1
1, 2, 3, 4, 5, 6, 32942, 103302, 142489, 178248, 263180, 361369, 362370, 378454, 540929, 540940, 567333, 567337, 590697, 693302, 723659, 726195, 743217, 829792, 888934, 1070221, 1073830, 1074177, 1083411, 1083738, 1090352, 1106956, 1129738, 1139557, 1139881, 1201762, 1249562 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Robert Israel, Table of n, a(n) for n = 1..1000

EXAMPLE

32942 in base 7 is 165020; in base 8 is 100256; and in base 9 is 50162. The set of digits for all three is {0, 1, 2, 5, 6}.

MAPLE

filter:= proc(n) local S;

  S:= convert(convert(n, base, 9), set);

  nops(S intersect {7, 8})=0 and evalb(convert(convert(n, base, 8), set)=S) and evalb(convert(convert(n, base, 7), set)=S)

end proc:

select(filter, [$1..6, seq(seq(9*a+b, b=0..6), a=1..7*9^5-1)]); # Robert Israel, Sep 11 2017

MATHEMATICA

Select[Range[5/4*10^6], Function[k, SameQ @@ Map[Union@ IntegerDigits[k, #] &, {7, 8, 9}]]] (* Michael De Vlieger, Sep 10 2017 *)

PROG

(PARI) isok(n) = my(s7 = Set(digits(n, 7)), s8 = Set(digits(n, 8)), s9 = Set(digits(n, 9))); (s7 == s8) && (s8 == s9); \\ Michel Marcus, Sep 09 2017

CROSSREFS

Subsequence of A037438.

Sequence in context: A153678 A004901 A004912 * A164699 A228050 A308070

Adjacent sequences:  A292122 A292123 A292124 * A292126 A292127 A292128

KEYWORD

nonn,base

AUTHOR

Paul Lusch, Sep 08 2017

EXTENSIONS

More terms from Michel Marcus, Sep 09 2017

STATUS

approved

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Last modified July 24 04:08 EDT 2019. Contains 325290 sequences. (Running on oeis4.)