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%I #19 Oct 05 2014 04:01:10
%S 1,8,15,64,7069,229826,62906548,104509874538,209233407362,
%T 474536678820,2653613575299,14802269029898
%N Positions at which A090895 (a(1) = 1 then a(n) = a(n-1)/2 if a(n-1) is even, a(n) = a(n-1) + n otherwise) reach the value of 1.
%C It seems that this sequence is infinite.
%e Example: the sequence a(1)=1 then a(n)=a(n-1)/2 if a(n-1) is even, a(n) = a(n-1) + n otherwise goes 1, 3, 6, 3, 8, 4, 2, 1, 10, 5, 16, 8, 4, 2, 1, etc... which has ones at 1, 8, 15, 64, etc...
%o (Haskell)
%o import Data.List (elemIndices)
%o a185038 n = a185038_list !! (n-1)
%o a185038_list = map (+ 1) $ elemIndices 1 a090895_list
%o -- _Reinhard Zumkeller_, Mar 02 2012
%Y Cf. A090895.
%K more,hard,nonn
%O 1,2
%A _Sergio Pimentel_, Mar 01 2012
%E a(8)-a(12) from _Hiroaki Yamanouchi_, Oct 04 2014
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