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%I #12 Feb 20 2019 09:48:03
%S 1,2,3,5,4,7,6,13,9,24,8,26,10,28,29,34,11,39,12,65,16,36,14,41,17,43,
%T 31,55,15,86,18,45,44,57,21,84,19,59,33,78,20,243,22,98,62,82,23,113,
%U 25,80,37,96,27,115,32,129,46,104,30,164,35,106,72,108,40
%N Smallest m such that A257339(m) = n.
%C A257339(a(n)) = n.
%H Reinhard Zumkeller, <a href="/A257455/b257455.txt">Table of n, a(n) for n = 1..10000</a>
%o (Haskell)
%o import Data.List (elemIndex); import Data.Maybe (fromJust)
%o a257455 = (+ 1) . fromJust . (`elemIndex` a257339_list)
%Y Cf. A257339.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Apr 24 2015