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a(n) = A007089(A262411(n)).

See A262411.

(Haskell)

import Data.List (inits, tails, intersect, delete)

a262412 n = a262412_list !! (n - 1)

a262412_list = 1 : f [1] (drop 2 a030341_tabf) where

f xs tss = g tss where

g (ys:yss) | null (intersect its $ tail $ inits ys) &&

null (intersect tis $ init $ tails ys) = g yss

| otherwise = (foldr (\t v -> 10 * v + t) 0 ys) :

f ys (delete ys tss)

its = init $ tails xs; tis = tail $ inits xs

-- Reinhard Zumkeller, Sep 22 2015

Cf. A030341, A007089, A262411.

nonn,changed,base

allocatedA262411 forin Reinhardternary Zumkellerrepresentation.

1, 10, 11, 12, 2, 20, 22, 21, 100, 101, 102, 110, 111, 112, 120, 121, 122, 200, 202, 201, 212, 210, 221, 211, 222, 220, 1002, 1001, 1000, 1010, 1011, 1012, 1021, 1020, 1101, 1022, 1102, 1110, 1100, 1111, 1112, 1120, 1121, 1122, 1201, 1200, 1211, 1202, 1212

1,2

Reinhard Zumkeller, <a href="/A262412/b262412.txt">Table of n, a(n) for n = 1..10000</a>

allocated

nonn

Reinhard Zumkeller, Sep 22 2015

approved

editing

allocated for Reinhard Zumkeller

allocated

approved