Tuesday, July 21, 2009

1331

1331 is a perfect cube.

1331 = 113 = (13 – 3 + 1)3 = (1 + 3 x 3 – 1)3.

1331 is that smallest cube (other than 1) containing only odd digits. It is also the smallest cube having every digit it contains exactly twice

1331 = 192 + 212 + 232.

1331 = 113 = 439 + 443 + 449 is the smallest solution of three consecutive primes summing to the third power of a prime.


A partial solar eclipse occurred on July 5 in the year 1331.

Source: The Penguin Dictionary of Curious and Interesting Numbers, rev. ed., by David Wells.
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1 comment:

  1. Felice LuftscheinJuly 21, 2009 at 12:37 PM

    This seems wrong:
    1331 = 11^3 = (13 – 3 + 1)^3 = (1 + 3 + 3 + 1)^3.

    Shouldn't it be =(1 + 3 x 3 + 1)^3?

    ReplyDelete