A059809 - OEIS

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A059809

Numbers that do not contain exactly the same digits in two different smaller bases.

2, 3, 4, 5, 6, 8, 10, 12, 14, 18, 20, 24, 32, 48, 60, 72, 168, 720

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Also numbers that cannot be expressed as the two-digit numbers a b (base r) and b a (base s) for two different smaller bases r and s (i.e., 2-digit "reversals"), and the numbers that cannot be expressed as "reversals" of any length for two different smaller bases. I can prove this. - Francis J. McDonnell, Jul 28 2015

LINKS

Table of n, a(n) for n=1..18.

Sascha Kurz, A059809 is finite (shows that there are no other terms) [Broken link]

EXAMPLE

8 written in bases 2 through 7 is 1000, 22, 20, 13, 12, 11 and none of these are permutations of another one.

CROSSREFS

Cf. A059808.

Sequence in context: A056864 A029032 A218906 * A327634 A121492 A182418

Adjacent sequences: A059806 A059807 A059808 * A059810 A059811 A059812

KEYWORD

base,nonn,fini,full

AUTHOR

Erich Friedman, Feb 24 2001

EXTENSIONS

More terms from Naohiro Nomoto, Oct 04 2001, who remarks that there are no others < 10000.

Offset set to 1 by Michel Marcus, Aug 03 2015

STATUS

approved