77th putnam competition

Todays the day. Putnam has finally arrived. Any of you pseudomathematicians going to be participating?

Yup, getting ready for it right now.

The kind of problems they put on those things aren't appealing enough to waste hours and hours on study sessions prepping for

I'm not bright enough to get more than like 1-2 questions even with intensive study for it

I know the series on the bottom track has a sum of -1/12. Insofar as each set of kills on the bottom can be brought into a 1:1 cardinality with the individual kills with the top, does this still favor the bottom from from a by-the-numbers utilitarian standpoint?

A1 was easy as fuck, anyone solve A5?

> being amerifat
No thanks, but I'd still want to look at the problems if anyone has them

Just finished my morning sesh, thought it went bretty well. Everyone walked out saying A1 was easy, but I didn't spend any time on it, which was a bummer. (Was on my next-to-do list, too).

Anybody work that tile problem? I kept reducing down to a 3x3 with some wiggle room, but couldn't reason a pattern I liked out.

Also, how'd it go for everyone? I'm hoping they have some complex or Fourier stuff on the next part, cuz as a EE its like my only edge you math guys

I definitely solved A1, worked on the group theory question for two hours with no solution.

Did anyone else get 8 on A1?

Thats what the people who did it in my group were saying. Damn, really really wish I gave it the time of day

Yup, it was 8.

Any one answer A2

Which was A2?

The limit of M(n)

how would this work?
1/12 of a person would be born?

Oh, I spent a good time on that. Tried a few different ways, but ultimately I think breaking it/solving into factorials make the most sense to me. Seemed to me that ... now that I'm typing this, seems to me I'm dumb because I just found that M[n] tends towards infinity as n does, but didn't check for coefficients or anything.

I got 1 as an ans, others in my group got "2" and "2 or 4" as an ans

Hmmm we got 1 and some weird (3+sqrt (5))/2

How did a sqrt fall out of a binomial? I mean when multiplying integers by integers, that seems like it would be a red flag

OP here, finished. Submitted 9 of the 12 problems with confidence. First section was easy, by the past test standards. The latter half was pretty much what was expected. The series at the very end was especially quite fun...

'squarish'

squarish

The sqrt answer is correct.

The triforce question was pretty dope, considering I usually suck at all things geometry.

Got a1 and b1
Mechanical engineer at shitty state school
>2 question min or you're worse than a bad engineer

Uh solving the inequality gives you a polynomial which is where the sqrt came from, we are super unsure about that answer just figured I'd mention it

Yeah, wording the triforce proof was challenging for me since i havent proved anything in geometry but i got through it.

How many did you all answer? Feel confident you got the right amswer? I solved A1 and B3 and proved B1 was a convergent series, but ran out of time before i could calculate the sum.

this was correct.
anyone get b3?

(3 + sqrt(5))/2 is the correct answer.

B1's sum converged to e-1. Observe that e^(x_n+t) = e - (x_0 + x_1 + ... + x_n) and let n go to infinity

I just wrote "trivial" for all of them. Got the highest score.

sorry, left hand side should be e^(x_n+1)

Yeah i had 10 minutes left after proving convergence and didnt see that.

>tfw starting to realize that doing better than 95% of everyone at my shit tier state university does not translate to being intelligent enough to solve these problems

got A1, would've got the binomial coefficient one if I was more efficient with time. I got stuck on the expected value of the determinant for the B section. oh well. i'll study more next year.

I tried the group theory one and coulnt get anywhere. Binomial was so easy

QUICKBUMP

lol

participated. didn't do well buttfuckit I tried.

I actually laughed when I read squarish on that one question

also; what'd you assholes get for A3?