Quiz 33: Find the index of first even element from a series

Problem:

For 1st row, element of a series is 1, for 2nd row, elements are 1,1,1. From 3rd row onwards, series increases by 1-1 elements at left and right of previous row such that each element is sum of 3 elements of above row(ie element immediately above and elements to left and right).
ie
1st row-                          1
2nd row-                    1   1   1
3rd row-                1   2   3   2   1
4th row-            1   3  6   7   6    3   1 (and so on)

Find the index of 1st element which is even for Nth row. Index starts with 1.

Input Format: 

first line, T, contains number of test cases

T lines containing N

Output Format: 
Index of first even element for N

Constraints: 
N>2

Sample Input

4
3
4
8
98

Sample Output:
2
3
3
4

Explanations:
for 4, series is 1 3 6 7 6 3 1, so 6 is first even number and index is 3.

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Solution:

@out=();
chomp($t=<STDIN>);
for($i=0;$i<$t;$i++)
    {
    chomp($n=<STDIN>);
    if($n%2 == 1)
{
push(@out,2);
next;
}
    $trd=$n*($n-1);
    $trd=$trd/2;
    if($trd % 2 eq 0)
{
push(@out,3);
next;
}
    push(@out,4);
    }
foreach(@out)
{
print "$_\n";
}

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Tips:

If N is odd, answer is 2 always. 3rd elements is n(n-1)/2, check if this is even->answer is 3. Otherwise answer is 4 always.