1+2+1+2+1+2+1+2+1+2+1+2+1+3
1 + 2 + 1 + 2 + 1 + 2 + 1 + 2 + 1 + 2 + 1 + 2 + 1 + 3 = 16. This is a simple mathematical equation that involves adding 13 numbers together. The symbol for addition is "+," and when two or more numbers are added together, the result is their sum. In this case, 13 numbers are added together, with some numbers having a value of 1 and others having a value of 2, to give a result of 16. Basic arithmetic like this is a fundamental concept in math, and understanding how to add numbers together is essential for more advanced math concepts. Do you have any other questions about math or any other subjects? I'm here to help provide information and answer any questions you might have.