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%I #14 Nov 29 2019 20:52:52
%S 5,6,11,12,28,60,152,388,780,2036,4076,8156,16316,32636,66232,169612,
%T 339228,1244808,4856004,14568120,56648484,190791072,866874960,
%U 4084880112,16342519392,73816544592,305811402048,1732931293824,10145637246528,52715820454848
%N a(n) = A129152(n) / 5^5, where A129152 is the trajectory of 5^6 under A003415, the arithmetic derivative.
%F a(n+1) = A129283(a(n)), a(0) = 5.
%F a(n) = A090635(n+3) / 4, i.e., the trajectory of 20 under A003415, divided by the common factor 4. - _M. F. Hasler_, Nov 27 2019
%o (Haskell)
%o a129286 n = a129286_list !! n
%o a129286_list = iterate a129283 5 -- _Reinhard Zumkeller_, Nov 01 2013
%Y Cf. A129284, A129285, A051674.
%K nonn
%O 0,1
%A _Reinhard Zumkeller_, Apr 07 2007