**Given:**

The sequence is
an=1(n+1)!
. (1)

**Calculation:**

Obtain the first term of the sequence.

Substitute 1 for *n* in equation (1).

a1=1(1+1)! =12! =12

Thus, the first term of the sequence is
a1=12_
.

Obtain the second term of the sequence.

Substitute 2 for *n* in equation (1).

a2=1(2+1)! =13! =16

Thus, the second term of the sequence is
a2=16_
.

Obtain the third term of the sequence.

Substitute 3 for *n* in equation (1).

a3=1(3+1)! =14! =124

Thus, the third term of the sequence is
a3=124_
.

Obtain the fourth term of the sequence.

Substitute 4 for *n* in equation (1).

a4=1(4+1)! =15! =1120

Thus, the fourth term of the sequence is
a4=1120_
.

Obtain the fifth term of the sequence.

Substitute 5 for *n* in equation (1).

a5=1(5+1)! =16! =1720

Thus, the fifth term of the sequence is
a5=1720_
.

Therefore, the first five terms of the sequence are
12,16,124,1120,1720
.