0, 1, 2, 10, 11, 12, 20, 21, 22, 100, 101, 102, 110, 111, 112
The sum of the first 5 numbers is 15. 1+2+3+4+5=15
They are 1, 2, 3, 4, 5, 6, 7, 8, 10, 11, 12, 13, 14, 15 and 16.
You cannot find the first 15 prime numbers by dividing by 2 and 3. This method would not identify 25 as being a composite.
In base 3, the counting numbers are represented using the digits 0, 1, and 2. The first 15 counting numbers in base 3 are: 0, 1, 2, 10, 11, 12, 20, 21, 22, 100, 101, 102, 110, 111, and 112. Each place value increases by powers of 3, similar to how place values increase by powers of 10 in the decimal system.
The first six triangular numbers are 1, 3, 6, 10, 15 and 21.
First five whole numbers are: 0 1 2 3 4
1, 2, 3, 4, 5, 6, 10, 11, 12, 13, 14, 15, 16, 20, 21...
0, 1, 2, 3, 10, 11, 12, 13, 20, 21, 22, 23, 30, 31, 32, 33
The numbers are 15 and 3. 15 * 3 = 45 15 + 3 = 18
They all relate by adding up the 6+6+3=15 You can not get to the sum of 15 is you don't have the first 3 numbers to add up.
1, 3, 6, 10, 15, 21
1, 3, 6, 10, 15, 21