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A075120 Number of steps to reach the first integer (= A075121(n)) starting with n/floor(sqrt(n)) and iterating the map x -> x*ceiling(x), or -1 if no integer is ever reached. 2

%I #12 Jan 16 2022 08:30:44

%S 0,0,0,0,2,0,1,0,0,5,2,0,3,2,0,0,3,3,2,0,2,1,3,0,0,8,3,5,2,0,3,2,5,3,

%T 0,0,6,2,2,4,2,0,5,3,1,4,2,0,0,7,12,5,11,12,2,0,4,3,9,12,6,16,0,0,3,7,

%U 8,4,4,4,2,0,2,4,5,1,5,2,5,0,0,7,3,22,3,3

%N Number of steps to reach the first integer (= A075121(n)) starting with n/floor(sqrt(n)) and iterating the map x -> x*ceiling(x), or -1 if no integer is ever reached.

%C Starting with A073890(n)/A075119(n).

%e a(13)=3 since 13/floor(sqrt(13)) = 13/3 -> 65/3 -> 1430/3 -> 227370 = A075121(13).

%Y Cf. A068119, A073524, A075102, A075107, A075121.

%K nonn

%O 1,5

%A _Reinhard Zumkeller_, Sep 03 2002

%E More terms from _Jinyuan Wang_, Jan 15 2022

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Last modified April 25 12:53 EDT 2024. Contains 371969 sequences. (Running on oeis4.)