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# what exactly does the (4n) stand for?

what exactly does the (4n) stand for?

## 1 Answer

the 4n means every 4th element. the syntax is an + b, where a and b are integers and the first index is 1. some examples from the docs: n is every element, 2n is every other element, the evens, 2n+1 is every other element, but starting at 1, so the odds, 3n+4 is every 3rd element, starting at element 4, so 4, 7, 10 etc. you can also use 0n + b to select a particular element, so 5 would be the fifth element only, 2 would be the second element only, etc.