# Is it a geometric sequence or not?

## Jelly, 4 bytes

Ṣ÷ƝE


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Thanks to fireflame241 for pointing out a mistake

### How it works

Ṣ÷ƝE - Main monadic link, takes an array as input
- e.g                            A = [2, 8, 4] or   A = [2, 6, 14]
Ṣ    - Sort                               [2, 4, 8]          [2, 6, 14]
Ɲ  - Over overlapping pairs [x, y]...   [[2, 4], [4, 8]]   [[2, 6], [6, 14]]
÷   - ...divide x by y?                  [0.5, 0.5]         [0.33, 0.43]
E - Is the list all the same?          1                  0


## J, 1514 13 bytes

1=&#&=2%/\/:~


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-1 byte thanks to xash

-1 byte thanks to Bubbler

• 1= Does one equal...
• &#&= the length of the uniq of...
• 2%/\ the list created by dividing each element by its right neighbor in the input list...
• /:~ sorted.

## APL (Dyalog Unicode), 25 19 bytes

{~∨/⌈(⊣-⊃)2÷/⍵[⍋⍵]}


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⍵[⍋⍵]      ⍝ sort ⍵
2÷/        ⍝ Take the quotient of all consecutive pairs
⍝ Check if all are equal:
(⊣-⊃)       ⍝ Subtract the first quotient
~∨/⌈        ⍝ Are all 0?