Identify the numbers that occur in the series 2, 10, 30, 68, 130, ... Choose the correct answer from the options given below.

1.738

2.349

3.520

4.222

A1, 2 and 3 only

B2, 3 and 4 only

C1, 3 and 4 only ✓ Correct

D1, 2 and 4 only

Correct answer: (C) 1, 3 and 4 only

Explanation

The numbers 738, 520 and 222 occur in the series.

Each term follows n^3 + n: 1+1, 8+2, 27+3, 64+4, 125+5.

738 = 9^3 + 9 = 729 + 9.

520 = 8^3 + 8 = 512 + 8 and 222 = 6^3 + 6 = 216 + 6.

349 is not of the form n^3 + n.

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