A261794 a(n) is the smallest nonzero number that is not a substring of n in decimal representation.

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, 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, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1

Offset: 0

Author

Reinhard Zumkeller, Sep 01 2015

Keywords

• nonn
• base

Comments

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

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 0..10000

Crossrefs

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

Programs

Haskell

import Data.List (isInfixOf)
a261794 x = f $ tail a031298_tabf where
   f (cs:css) = if isInfixOf cs (a031298_row x)
                   then f css else foldr (\d v -> 10 * v + d) 0 cs

Extensions

Name corrected by Álvar Ibeas, Sep 08 2020