+0

+1
201
3
+177

How many positive integers less than 2008 have an even number of divisors?

May 6, 2021

#1
+2209
0

If they have an odd number of divisors, they're prime, there are 44 prime numbers less than 2008. sqrt(2008)

2008-44 = 1964

=^._.^=

May 6, 2021
#2
+2196
+1

Hi Catmg,

Your text should read: “If they have an odd number of divisors, they're perfect squares.

How many positive integers less than 2008 have an even number of divisors?

So ...

$$2007-\lfloor\sqrt{2007}\rfloor = 1963$$

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Catmg, you have wonderful math skills. You present excellent solutions to a fairly broad range of math questions.

GA

GingerAle  May 6, 2021
#3
+2209
+1

Aww, thank you. :))