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"Autotomy numbers" have two properties: (1) they have distinct decimal digits, and (2) subtracting their last digit from the remaining part produces another autotomy number (the numbers 1 to 9 are considered to be part of the sequence).
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%I #12 May 25 2019 11:57:02

%S 1,2,3,4,5,6,7,8,9,10,20,21,30,31,32,40,41,42,43,50,51,52,53,54,60,61,

%T 62,63,64,65,70,71,72,73,74,75,76,80,81,82,83,84,85,86,87,90,91,92,93,

%U 94,95,96,97,98,210,243,254,265,276,287,298,309,310,320,321,342,354,364,365,375,376,386,387,397,398,408,409,410,419,420,421

%N "Autotomy numbers" have two properties: (1) they have distinct decimal digits, and (2) subtracting their last digit from the remaining part produces another autotomy number (the numbers 1 to 9 are considered to be part of the sequence).

%C There are exactly 41943 autotomy numbers. For autotomy numbers with 10 distinct decimal digits, see the Crossref section.

%H Jean-Marc Falcoz, <a href="/A308393/b308393.txt">Table of n, a(n) for n = 1..41943</a>

%H Eric Angelini, <a href="https://cinquantesignes.blogspot.com/2019/05/pandigitaux-et-saucissons.html">Pandigitaux et saucissons</a> (in French).

%e a(56) = 243 is in the sequence because 24-3 = 21 and 21 is already in the sequence. The same is true for a(57) = 254 as 25-4 = 21 too.

%Y Cf. A308377 (autotomy numbers with 10 distinct decimal digits).

%K base,nonn,fini

%O 1,2

%A _Eric Angelini_ and _Jean-Marc Falcoz_, May 24 2019