Abundant number

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An abundant number is a number n for which the sum of the divisors of n is greater than 2n. 12 is an abundant number because 1 + 2 + 3 + 4 + 6 + 12 > 24. 18 is also an abundant number because 1 + 2 + 3 + 6 + 9 + 18 > 39. The series is in the Online Encyclopedia of Integer Sequences (Sloane) as A005101. The first 14 abundant numbers are:12,18,20,24,30,36,40,42,48,54,56,60,66,72. The first 14 odd abundant numbers are:945,1575,2205,2835,3465,4095,4725,5355,5985,6615,7245,7875, 8505.