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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.
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%I #8 Jan 16 2022 11:08:25

%S 0,1,2,2,18,0,3,2,3,3,26,1,9,3,7,3,6,3,56,10,9,15,42,2,10,3,3,0,38,17,

%T 79,3,27,16,8,8,200,76,4,3,36,2,4,15,4,51,11,2,4,6,22,42,43,5,25,2,4,

%U 103,37,17,18,20,8,3,22,25,225,59,6,13,20,4,182,13,8

%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. A000203, A009194, A073524.

%K nonn

%O 1,3

%A _Reinhard Zumkeller_, Oct 05 2002

%E a(20) corrected by and more terms from _Jinyuan Wang_, Jan 15 2022