Puper love Aishwarya of Architecture dept. He thinks facebook is the best way to tell her his feelings. So he writes a message and sends her on Facebook. But he don't know that the message will go in message request or spam message section. But he also knows that Aishwarya looks in these section rarely. So he is not sure whether the message will be seen or not. He knows the fact that she will see his message if his following algorithm works :-

He constructs a tree by taking the whole message as root and keeps on dividing in two half parts unless string of length one is left.

for example:-

if message is of length,l = 6, then on first division of the message, the first message contains string of length, mid=(1+6)/2 = 3 and another half will be of length l-mid = 6-3 = 3.

Similarly, the obtained messages are further divided (see the picture below).
He considers every divided part as a node of the tree. Then he takes all the nodes with no further children (say it leaf node) and sum the corresponding values of all the nodes.

If the value is prime then the message is seen otherwise the message is unseen.

Help Puper in conveying the message to Aishwarya and in knowing the status of the message.
INPUT:-
First line of input contains the number of test cases t and in each case the first line contains n , the length of the message and next line contains the messages S of length n.
OUTPUT:-
For each test case output whether the message is "seen" or "unseen" (without quotes).
CONSTRAINTS:-
1<=t<=50
1<=n<=100000
The message consists of lowercase (a-z) characters only and no whitespace is there in the messages. The values of the character are as a = 1 to z = 26.