Question 254471
<font face="Garamond" size="+2">


The odd primes are all of the primes except for 2. 5 is the third prime number and the second odd prime number, and is therefore a factor of the product of the first 2002 odd prime numbers.  The product of 5 and any odd number ends in 5.  The product of any two odd numbers is odd, so the product of the first odd prime number, namely 3 times the product of the 2000 prime numbers subsequent to 5 must be odd.  The product of that number and 5 is the product of the first 2002 odd primes, and it must end in 5.


Super double plus extra-credit:  What is the last digit of the first 1583 primes?


John
*[tex \LARGE e^{i\pi} + 1 = 0]
</font>