%I #15 Mar 26 2015 13:59:35
%S 1,2,9,5,6,36,10,11,12,100,17,18,19,20,225,26,27,28,29,30,441,37,38,
%T 39,40,41,42,784,50,51,52,53,54,55,56,1296,65,66,67,68,69,70,71,72,
%U 2025,82,83,84,85,86,87,88,89,90,3025,101,102,103,104,105,106,107
%N Smallest m such that A256188(m) = n.
%C A256188(a(n)) = n and A256188(m) != n for m < a(n).
%H Reinhard Zumkeller, <a href="/A253169/b253169.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = if n triangular then n^2 else A004202(n + 1 - A002024(n)).
%o (Haskell)
%o import Data.List (elemIndex); import Data.Maybe (fromJust)
%o a253169 = (+ 1) . fromJust . (`elemIndex` a256188_list)
%Y Cf. A256188, A000537, A010054, A000290.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Mar 26 2015