Ao, Eo, Io, _ ? _, Uo

What is the missing entity. Provide the reasoning to back up your answer.

I have considered Oo already but that doesn't seem to be the required solution. Please help.

  • 3
    $\begingroup$ Welcome to Puzzling! Where is this puzzle from? If you don't know the answer, I suspect it will be little more than a mind-reading exercise with this little information. $\endgroup$ – Deusovi Aug 19 '18 at 15:14
  • $\begingroup$ Fond or find, which one $\endgroup$ – Duck Aug 19 '18 at 15:32
  • 1
    $\begingroup$ @Deusovi Apparently it's a BlackRock Software Engineering interview question. $\endgroup$ – lovemathboy Aug 19 '18 at 15:32
  • $\begingroup$ @Duck: Fill the blank: Fand, fend, find, ____, fund. $\endgroup$ – M Oehm Aug 19 '18 at 15:33
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    $\begingroup$ Who says Oo is not the required solution? $\endgroup$ – xhienne Aug 19 '18 at 15:40

Ao, Eo, Io, Mo, Qo, Uo


The first _ is "Mo", the ? is "," and the second _ is "Qo"


A is 1, E is 5, I is 9 and U is 21. "The Hilbert numbers or S-numbers are numbers of the form 4n + 1" M is 13 and Q is 17, completing the sequence


Is this an interview or test question?

If so, perhaps it's:

Qo or theta-o

Ao, Eo and Io are all

astronomical variables for orbit equations and crazy three-body problem math...


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