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%I #13 Jul 14 2022 12:50:08
%S 0,0,1,2,3,5,6,4,9,10,9,14,5,18,10,7,26,9,29,30,6,33,27,41,24,15,50,
%T 53,18,14,55,50,7,65,34,69,14,74,26,81,78,9,86,29,89,90,18,48,98,33,
%U 10,45,105,113,38,12,81,41,25,8,26,134,46,35,47,68,146,45
%N Smallest k such that A014657(n) divides 2^k + 1.
%H Reinhard Zumkeller, <a href="/A195610/b195610.txt">Table of n, a(n) for n = 1..1000</a>
%F 2^a(n) + 1 = A337220(n)*A014657(n), n>=1. - _Wolfdieter Lang_, Aug 22 2020
%o (Haskell)
%o import Data.List (elemIndex)
%o import Data.Maybe (catMaybes)
%o a195610 n = a195610_list !! (n-1)
%o a195610_list = catMaybes $ map k [1..] where
%o k x = elemIndex 0 $ map (`mod` x) $ take (fromInteger x) a000051_list
%Y Cf. A000051, A014657, A195470, A337220.
%K nonn
%O 1,4
%A _Reinhard Zumkeller_, Sep 21 2011