How many presidents have not had pets?
3
2
2
2
2
3
2
3
2
4
3
2
4
1
3
2
5
4
1
3
2
5
4
1
3
2
5
4
1
3
2
7
5
4
1
3
2
7
5
4
1
3
0
2
7
5
4
1
3
2
7
5
4
0
1
3
2
7
5
4
1
0
3
2
7
5
4
1
3
6
0
2
7
5
4
1
8
3
6
2
7
5
4
0
1
8
3
6
2
7
5
4
1
8
0
3
6
2
7
5
4
1
9
8
3
6
7
5
4
1
9
8
3
6
7
5
4
1
9
8
3
6
13
7
5
4
1
9
8
3
6
13
7
5
4
1
9
8
6
13
7
5
4
1
9
8
6
13
7
5
1
9
11
8
6
13
7
5
9
11
8
6
13
7
9
11
8
6
13
7
10
9
11
8
6
13
7
10
9
11
8
6
13
10
9
11
8
6
13
12
10
9
11
8
6
13
12
10
9
11
213