PERFECT NUMBERS
The Greeks called the number 6 the first "perfect number." A perfect number is one where
all the divisors (except the number itself) add up to the number, e.g. the divisors of six are
1, 2, and 3, and 1 + 2 + 3 = 6. Following are the first dozen perfect numbers; number twelve
has 77 digits; these are historically important because in the more than 2,000 years that elapsed
between the time the Greeks made their determination and 1952, when computers were first
used for this purpose, mathematicians discovered a total of only twelve perfect numbers; we now
know thirty-seven (the highest having 1,819,050 digits):
6.
28.
496.
8128.
33550336.
8589869056.
137438691328.
2305843008139952128.
2658455991569831744654692615953842176.
191561942608236107294793378084303638130997321548169216
13164036458569648337239753460458722910223472318386943117783728128.
14474011154664524427946373126085988481573677491474835889066354349131199152128.
More on Perfect Numbers
The Mersenne Prime Race
. . . . .as ref'd by Martin Fouts in news:misc.writing
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