The sum of the first consecutive 800 odd numbers is 640,000.
9, 11, 13, 15, 17, 19, 21
640000. First odd number is 1, 800th odd number is 1599, giving their sum: sum = number_of_numbers x (first_number + last_number) ÷ 2 = 800 x (1 + 1599) ÷ 2 = 640000
The first 20 odd numbers are: 13579111315171921232527293133353739.
The first 100 odd whole numbers are: 13579111315171921232527293133353739414345474951535557596163656769717375777981838587899193959799101103105107109111113115117119121123125127129131133135137139141143145147149151153155157159161163165167169171173175177179181183185187189191193195197199.
The first 85 odd numbers are: 1 3579111315171921232527293133353739414345474951535557596163656769717375777981838587899193959799101103105107109111113115117119121123125127129131133135137139141143145147149151153155157159161163165167169.
27 + 29 = 56.
The sum of the first 300 odd numbers is 90,000
The sum of the first 1,000 odd numbers is 1,000,000.
The sum of the first 50 odd numbers is 2,500.
The sum of the first 40 odd numbers is 1,600.
The sum of the first 153 odd numbers is 23,409.
The sum of the first 8,000 odd numbers 64,000,000.