6

I know there is a term for a number that is the power of 2, such as 8, 32, 128, 4096 -- but it slipped my mind.

12
  • 2
    Just for the record - is there a reason you skipped every other power of two in your example?!!
    – Fattie
    Jul 11, 2011 at 8:34
  • 1
    Actually 4096 fits the pattern, because it's a power of 2.
    – Alenanno
    Jul 11, 2011 at 8:58
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    @Alenanno: I think the pattern Joe meant was the standard sequence of powers of two are 2,4,8,16,32,64,128,256,512 .. and Jen used alternate powers in the post 8,32,128 and then jumped to 4096.
    – JoseK
    Jul 11, 2011 at 9:40
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    I'd call them round numbers, but that may be a programmers affliction. ;)
    – MSalters
    Jul 11, 2011 at 10:16
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    @Alenanno Just for what it's worth. Read my comment again. It says "In your example", the example being: "8, 32, 128, 4096". OK?
    – Fattie
    Jul 11, 2011 at 15:44

2 Answers 2

24

A "power of two" seems like a good name.

Although 'exponent' has been suggested, it is not correct

The relationship is quite simple, though:

3 is the exponent which generates the power of two   8       (23 = 8)

12 is the exponent which generates the power of two 4096  (212 = 4096)

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  • 1
    Indeed. Any mathematical documentation I can find refers to them as powers of two. Jul 11, 2011 at 9:00
  • 7
    "It's more precise than saying an exponent." - No, "exponent" would simply be wrong here, not just less precise. Why did you even mention it? It just muddies the waters. I could understand it if Jen had suggested it, and you were making a correction - but you're just correcting yourself here.
    – MT_Head
    Jul 12, 2011 at 10:00
  • @MT_Head, I agree. What I typed yesterday was just fastest gun in the west syndrome. I could edit my answer, but it seems a little late now.
    – pavium
    Jul 12, 2011 at 11:33
  • @pavium - Feel free to edit your answer! Remember, the whole reputation-points thing is (supposed to be) secondary to giving correct answers, not just for the OP but for future Googlers. In this case, a straight edit would make your answer identical with @Digital Powers', but perhaps an explanatory note? Future Googlers might not read the comments.
    – MT_Head
    Jul 12, 2011 at 16:39
8

In programming, especially graphics programming (textures), powers of two are sometimes referred to as POT, and non-powers of two as NPOT.

But obviously the word "pot" has strong connotations, and so this term can be used only in such a context unambiguously. Anywhere else, "power of two" is a much better choice.

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