Very challenging

What comes next in the series of numbers:

1, 2, 3, 4, ?

Good Luck 🙂

6

as in
1,2,3,4,?,6

6 as in factors of 12:

1,2,3,4,6,12

I concur with the others. The correct answer is 6.

Starting with n(1)=1, n(2)=2 and n(3)=3 we have n(i)=n(i-1)+n(i-3) for i=4 and upwards.

n(5) must therefore be 6.

well it could also be 5 because it is the next acending numeral and we were not instructed that it wasn't 5 in the question

That's one of the reasons I dislike these types of problems. Who's to say that one answer is more valid than another? I think '5' and '6' are equally valid. Any number that conforms to a natural or mathematical pattern must be considered a solution.