A375013 A cycle of length 6 when iterating x <- phi(sigma(x)).
1800, 2880, 3024, 3840, 3456, 2560
Offset: 1
Examples
phi(sigma(1800)) = 2880, ... phi(sigma(2560)) = 1800, so 1800 is in the sequence.
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phi(sigma(1800)) = 2880, ... phi(sigma(2560)) = 1800, so 1800 is in the sequence.
phi(sigma(27648)) = 30976, ... phi(sigma(34560)) = 27648, so 27648 is in the sequence.
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