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A075121 First integer reached when starting with n/floor(sqrt(n)) and iterating the map x -> x*ceiling(x) A075120(n) times, or -1 if no integer is ever reached. 3

%I

%S 1,2,3,2,60,3,14,4,3,1484710602474311520,220,4,227370,560,5,4,218790,

%T 268065,570,5,1008,33,1458660,6,5

%N First integer reached when starting with n/floor(sqrt(n)) and iterating the map x -> x*ceiling(x) A075120(n) times, or -1 if no integer is ever reached.

%C a(26) = 9.20120538...*10^191 is too large to be included in Data. - _Jinyuan Wang_, Jan 15 2022

%H Jinyuan Wang, <a href="/A075121/b075121.txt">Table of n, a(n) for n = 1..50</a>

%e n=13: after A075120(13)=3 steps 13/floor(sqrt(13)) = 13/3 -> 65/3 -> 1430/3 -> 227370, therefore a(13)=227370.

%Y Cf. A075103, A075108, A075120.

%K nonn

%O 1,2

%A _Reinhard Zumkeller_, Sep 03 2002

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Last modified August 17 12:30 EDT 2022. Contains 356189 sequences. (Running on oeis4.)