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%I #15 Sep 08 2022 08:46:22
%S 0,1,2,3,4,5,6,7,8,9,19,29,39,49,59,69,79,89,91,92,93,94,95,96,97,98,
%T 99,118,127,136,145,154,163,172,181,199,217,227,236,245,254,263,271,
%U 272,299,316,326,336,345,354,361,362,363,399,415,425,435,445,451
%N Numbers k such that the smallest digit of k is equal to the additive digital root of k (in base 10).
%C Numbers k such that A054054(k) = A010888(k).
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/DigitalRoot.html">Digital Root</a>
%t Select[Range@ 451, Min@ IntegerDigits@ # == FixedPoint[Total@ IntegerDigits@ # &, #] &] (* _Michael De Vlieger_, Jul 22 2018 *)
%o (Magma) [n : n in [1..10000] | (1+(n-1) mod 9) eq &+[Min(Intseq(n))]]
%o (PARI) isok(n) = (n==0) || (vecmin(digits(n)) == (n-1)%9+1); \\ _Michel Marcus_, Jul 23 2018
%Y Cf. A010888, A054054, A107085 (with "largest" digit instead of "smallest").
%K nonn,base
%O 1,3
%A _Jaroslav Krizek_, Jul 21 2018
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