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 A074970 Number of steps to reach the first integer starting with sigma(n)/n and iterating the map x -> x*ceiling(x), or -1 if no integer is ever reached. 0

%I

%S 0,1,2,2,18,0,3,2,3,3,26,1,9,3,7,3,6,3,56,11,9,15,42,2,10,3,3,0,38

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

%C a(p) = A073524(p) for primes p.

%e a(26)=3 since (26+13+2+1)/26=21/13 -> 42/13 -> 168/13 -> 168.

%Y Cf. A073524, A000203, A009194.

%K nonn

%O 1,3

%A _Reinhard Zumkeller_, Oct 05 2002

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Last modified December 14 01:03 EST 2019. Contains 329977 sequences. (Running on oeis4.)