They add up to 129
The sum of the first 50 whole numbers is 1,225.
The sum of the first 1,000 whole numbers is 499,500.
The sum of the first 40 whole numbers is 780.
The sum of the first 300 odd numbers is 90,000
The sum of the first 100 numbers, excluding zero, is 5,001.
The sum of the first 1,000 odd numbers is 1,000,000.
The sum of the first 10,000 even numbers is 100,010,000.
The sum of the first 13 odd numbers is 169.
The sum of the first nine odd numbers is 81.
The sum of the first 153 odd numbers is 23,409.
The sum of the first 40 odd numbers is 1,600.
The sum of the first 50 even numbers is 2,550.