Given that: a1=27, an=(an-1)+4 the second term will be: a2=a1+4 a2=27+4=31 The explicit formula for arithmetic sequence is given by: an=a+(n-1)d where: a= first term d=common difference n=nth term from the information given: a=27 d=31-27=4 thus the explicit formula will be: an=27+(n-1)4 an=27+4n-4 an=23+4n