Moderator Note: At the time that this question was posted, it was from an ongoing contest. The relevant deadline has now passed.
Suppose we have a triangle of numbers. Atop the triangle is 1: each number below it is determined by summing half of each of the numbers that it is supporting, and adding 1 to the sum. The first few layers in the triangle look like this:
1 3/2 3/2 7/4 10/4 7/4 15/8 25/8 25/8 15/8 31/16 56/16 66/16 56/16 31/16
The numbers on the edges are such that the number on either end of layer n is $\frac{2^n -1}{2^{n-1}}$. Can we write a generalization for any term in the pyramid, given that any term is the $k$th term in the $n$th row?
Original question and proof for middle term here: A pyramid of numbers
There is also this: Proof- central term of recursive pyramid
Perhaps a similar method could be used?
(Please explain the architecture of your solution, and how you came about it. I think that an answer that simply fits is FAR less valuable than an instance where we know WHY the answer is fitting. ) Perhaps this can be done with modifications to Pascal's triangle?
I have noticed something rather interesting- if we discard the denominators of the numbers in this pyramid, which are simply $2^{n-1}$ where $n$ is the row number, and leave all the numerators behind in the pyramid, then we can produce the nth line of the pyramid by taking the following pyramid(the following is a example, that produces the fourth line of the pyramid)
j h i e f g a b c d
If e= $\frac{a+b}{2}$, f= $\frac{b+c}{2}$, and so on and so forth, all characters in rows above the bottom one are the "average" of the two characters they are nested in. Then if we add a+b+c+d+e+f+g+h+i+j, we get 15a+ 25b+25c+15d/8. As you can see, the coefficients produce the fourth line in our pyramid. Similarly if we add the characters in a pyramid with base [abcde] and tip k we will get 31a+56b+66c+56d+31e/16 . The coefficients of a,b,c,d, and e are the terms in the fifth line of our pyramid. Can anyone think of WHY(what in the architecture of both pyramids) this correlation exists between these two seemingly disconnected pyramids, through connecting their production methods?