How can big-O notation be used to estimate the sum of the first n positive integers?

How many ancestors does a person have, in total, among the previous n generations of their relatives? (Assume every person has two parents, a person is their own ancestor and that one's parents comprise the n = 1 generation) Explain the relationship between your response and an unsigned binary number, what does each digit represent in the context of counting ancestors?

Convert these from hexidecimal decimal. Show all work. 1016= a216= ff16= 1416= 2d16=

Think of a number. Multiply it by 2. Add 2. Divide by 2. Subtract 1. How does the result compare with your original number? Will this work all the time? Explain your answer.