[seqfan] Observation on the divisors of 136
Jeremy Gardiner
jeremy.gardiner at btinternet.com
Fri Dec 29 23:33:29 CET 2017
Consider the divisors of 136 (A018299):
1, 2, 4, 8, 17, 34, 68, 136.
136 in binary is 10001000.
Reading off successive bits from the left we have:
1 1
10 2
100 4
1000 8
10001 17
100010 34
1000100 68
10001000 136
This prompts the question, what other numbers have this property?
i.e. Numbers whose successive binary shifted parts as decimal numbers are
identical to their ordered divisors.
Clearly, the powers of 2 have this property.
Also for example 10 in binary is 1010 giving 1, 2, 5, 10.
The sequence begins:
1, 2, 3, 4, 8, 10, 16, 32, ... but it is not A295296.
Regards,
Jeremy Gardiner
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