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A075428
Number of steps to reach the first integer (= A075429(n)) starting with 1 + 2/(n*(n+1)) and iterating the map x -> x*ceiling(x), or -1 if no integer is ever reached.
1
0, 2, 2, 7, 4, 3, 4, 8, 7, 41, 15, 15, 18, 10, 8, 17, 10, 12, 10, 5, 9, 9, 10, 11, 14, 39, 12, 33, 65, 9, 31, 6, 23, 26, 6, 71, 98, 22, 43, 20, 26, 4, 33, 12, 36, 128, 43, 18, 10, 81, 28, 54, 24, 12, 8, 38, 19, 10, 41, 36, 83, 32, 9, 9, 12, 13, 60, 58, 19, 32
OFFSET
1,2
EXAMPLE
a(5)=4 since 1 + 2/(5*6) = 1 + 1/15 = 16/15 -> 32/15 -> 32/5 -> 224/5 -> 2016=A075429(5).
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Sep 16 2002
EXTENSIONS
More terms from Jinyuan Wang, Jan 15 2022
STATUS
approved