The following sequence of numbers is used in a sorting algorithm called Shell  sort (https://en.wikipedia.org/wiki/Shellsort), which balances implementation complexity and performance. 1, 3, 7, 15, 31 … The n-th number in the sequence is equal to (2n - 1), where n is some positive  integer. Devise an algorithm to input an integer greater than 0 as n, and output the first n  members of this sequence.

Please help me with these questions. I am having trouble understanding what to do 

Programming language: (HTML, CSS, JavaScript)

Please Just draw the flowcharts and please provide preconditions and postconditions for each
solution you provide.

IMPORTANT: In Ex 13, 14,  and 15, you are not allowed to use strings. Instead, you should work
with numbers and mathematical operators, such as division, remainder, etc

Ex 13) The following sequence of numbers is used in a sorting algorithm called Shell 
sort (https://en.wikipedia.org/wiki/Shellsort), which balances implementation
complexity and performance. 1, 3, 7, 15, 31 …
The n-th number in the sequence is equal to (2n - 1), where n is some positive 
integer. Devise an algorithm to input an integer greater than 0 as n, and output the first n 
members of this sequence.

Ex 14) Devise an algorithm to input an integer greater than 1 as n, and output the first 
n valuesof the Fibonacci sequence. In Fibonacci sequence, the first two values 
are 0 and 1 and other values are sum of the two values preceding it. For 
instance, if the input is 4, the program should print 0, 1, 1, 2. As another 
example, if the input is 9, the program shouldoutput 0, 1, 1, 2, 3, 5, 8, 13, 21.
Learn more about applications of Fibonacci number in reallife here: http://
www.ijesi.org/papers/Vol(6)9/Version-3/B0609030714.pdf . There may be a
question on this in the pre-lab mini quiz!!

Ex 15) Devise an algorithm to input a positive integer, n, – and by using ‘*’ characters – 
output the figure below that has n rows, with 3 ‘*’ characters in the top row 
and 3*n charactersin the last row. For instance, if input is 5, the figure on the 
left (and if the input is 12, the figure on the right) should be generated by the
program