Write the first five terms of each of the sequences in and obtain the corresponding series:

a1 = a2 = 2, an = an-1 -1, n > 2


Here given, a1 = a2 = 2, an = an-1 -1, n > 2


a3 = a2 -1 = 2-1 = 1


a4 = a3 -1 = 1-1 = 0


a5 = a4 -1 = 0 -1 = -1


The first five numbers of the sequence are 2, 2, 1, 0 ,-1


The corresponding series is 2 + 2 + 1 + 0 + (-1) + ………


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