Genius Minds Wake Up !!!!

Answer this Question Correctly (#Brain Challenging#)

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1,1,2,3,8,?

What replaces the Question Mark "?"......

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The Answer is 15. Below is the logicThis is a series of Double Factorial.

Rule of Double Factorial.

If n is even, then

n !! = n ( n - 2)( n - 4)( n - 6) ... (4)(2)

If p is odd, then

p !! = p ( p - 2)( p - 4)( p - 6) ... (3)(1)

So, accrding to the above logic..

0!!=1

1!!=1

2!!=2

3!!=3

4!!=4*(4-2)=4*2=8

The value u hav to find is...

5!!=5*(5-2)*(5-4)=5*3*1=15.

So, the ansr is 15.