It is 1000*(1000+1)/2 = 500500
The sum of 1 through 250 is 31,375.
The sum of the numbers 1 through 27 is 378.
The sum of the numbers from 1 through 100 is 5,050.
The sum of the prime numbers between 1 and 1,000 (2-999) is 76,127.
It is 1000*(1000+1)/2 = 500500
1000+1000 =2000 because 1+1=2 than add three zeros
To get a list of the squares of the first 1000 numbers we can do:> [n^2 | n sum [n^2 | n
The sum of 1 through 250 is 31,375.
The sum of the numbers 1 through 27 is 378.
The sum of the numbers from 1 through 100 is 5,050.
1,000,000 * * * * * The 1st and 500th sum to (2*1-1)+(2*500-1) = 2*501 - 2 = 1000 The 2nd and 499th sum to (2*2-1)+(2*499-1) = 2*501 - 2 = 1000 There are 250 such sums So sum of all 500 odd numbers = 250*1000 = 250,000
The sum of the prime numbers between 1 and 1,000 (2-999) is 76,127.
500
1001
The sum of all the numbers 1 through 200 is 20,100.
That would be equal to the sum of all positive integers less than 1000 minus the sum of all positive multiples of three that are less than 1000. That would be equal to: (1000 + 1) * (1000 / 2) - 3 * (333 + 1) * (333 / 2) = 1001 * 500 - 1000 * 166.5 = 500500 - 166500 = 334000