Is the sum of 2009 + 2008 + 2007 + 2006 +. + 4 + 3 + 2 + 1 odd or even?

Is the sum of 2009 + 2008 + 2007 + 2006 +. + 4 + 3 + 2 + 1 odd or even?

2009 / 2 = 1004 so many out of a bit is 1003, the other before and after the addition, so and mantissa is 3 odd

1 + 2 + 3 + 4 +. + 2009 + 2010 odd number is positive, even number is negative, what is the result

Taking two numbers as a group, we can get a total of 2010 / 2 = 1005 groups
The sum of each group was - 1
So the result is - 1 / 1005 = - 1005

Is the result of the following formula odd or even? 1+2+3+4+… +2009+2010．

There are 1005 odd numbers and even numbers from 1 to 2010. According to even number + even number = even number, we can get even numbers 2, 4, 6 The sum of 20082010 is even, while 1, 3, 5 According to odd number + odd number = even number, odd number + even number = odd number, we can get 1, 3, 5 2007, 2009 this