# 2010-11 Mandelbrot Team Play Rd 1

Post date: Feb 10, 2011 11:28:22 PM

Here are the results for Mandelbrot Team Play. One of our team scored 24 points, which is the second highest.

Our team name is HUGE. Here's the key for comments.

B) Working backwards is a good problem solving strategy, but make sure to present solutions arguing forward from known information and facts.

C) Complete solution, or close enough; fine job.

D) The proof was difficult to decipher because of a confusing or illegible presentation, so less credit was awarded than might have been.

E) The paper merited few if any points, but the response was quite enjoyable to read!

F) The formula was either incorrect, or omitted, or perhaps not analogous to the one given in the previous part.

G) Your list accidentally went up to 32 instead of 31, giving a sum of 81 instead of 80.

H) Half the question was answered correctly; the other half was omitted or no headway was made.

K) Please don't refer to your work in the first part, since papers are separated during the grading process.

L) Fine answer, but more lengthy than necessary; it is OK to be more concise or cite previous results.

M) Mostly there; main ideas are correct but points deducted for missing details or too brief a proof.

N) Not bad; careless mistakes or a false statement tarnish an otherwise correct solution.

O) Omitted problem or no attempt at a proof.

P) Please do not refer to your proof written for another part. Include all work for a given part with that particular proof. (It is fine to quote the result of a previous part, however.)

Q) Your formula is correct; now explain how it follows from the identity presented in the first half of the problem.

R) On the right track or a few of the correct ideas present, so deserving of some credit.

S) One or more of the b(n) values were calculated incorrectly.

T) It is not true in general that b(n-k) = b(n)-b(k). The fact that b(31-k) = b(31) - b(k) is special and should be explained.

U) Your inductive step works when n+1 is odd, but one must also address the more difficult case where n+1 is even.

V) Your formula is correct, and you have good ideas for the first part, although it has not been completely explained.

W) On the wrong track or a very difficult approach, but warranting some credit.

X) You have shown that the equality holds for some values of r; now find an argument to show that it is always true.

Y) Little or no significant progress towards a solution (occasionally despite a fair amount of work), or misinterpretion of the question.

Z) Please clearly define any expressions or functions used in your formula.