SICP Exercise 1.27 (Carmichael Numbers)



Exercise 1.27.  Demonstrate that the Carmichael numbers listed in footnote 47 really do fool the Fermat test. That is, write a procedure that takes an integer n and tests whether an is congruent to a modulo n for every a<n, and try your procedure on the given Carmichael numbers.

SOLUTION

 The code and tests are here.

 Observations
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 The above program demonstrates that the Carmichael numbers 561, 1105....to 6601 fool the Fermat test. These are all composite numbers that pass the Fermat test.

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