A261794 - OEIS

%I #14 Sep 09 2020 11:29:28

%S 1,2,1,1,1,1,1,1,1,1,2,2,3,2,2,2,2,2,2,2,1,3,1,1,1,1,1,1,1,1,1,2,1,1,

%T 1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1,1,2,1,1,1,1,1,1,

%U 1,1,1,2,1,1,1,1,1,1,1,1,1,2,1,1,1,1

%N a(n) is the smallest nonzero number that is not a substring of n in decimal representation.

%C A261795(n) = a(A261793(n)).

%H Reinhard Zumkeller, <a href="/A261794/b261794.txt">Table of n, a(n) for n = 0..10000</a>

%o (Haskell)

%o import Data.List (isInfixOf)

%o a261794 x = f $ tail a031298_tabf where

%o    f (cs:css) = if isInfixOf cs (a031298_row x)

%o                    then f css else foldr (\d v -> 10 * v + d) 0 cs

%Y Cf. A007089, A031298, A261795, A261793, A261461, A261787.

%K nonn,base

%O 0,2

%A _Reinhard Zumkeller_, Sep 01 2015

%E Name corrected by _Álvar Ibeas_, Sep 08 2020