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2023 LMT Fall Guts Round p16-p27 - Lexington Mathematical Tournament

Source:

March 2, 2024
LMTalgebrageometrycombinatoricsnumber theory

Problem Statement

Part 6
p16. Let p(x)p(x) and q(x)q(x) be polynomials with integer coefficients satisfying p(1)=q(1)p(1) = q(1). Find the greatest integer nn such that p(2023)q(2023)n\frac{p(2023)-q(2023)}{n} is an integer no matter what p(x)p(x) and q(x)q(x) are.
p17. Find all ordered pairs of integers (m,n)(m,n) that satisfy n3+m3+231=n2m2+nm.n^3 +m^3 +231 = n^2m^2 +nm.
p18. Ben rolls the frustum-shaped piece of candy (shown below) in such a way that the lateral area is always in contact with the table. He rolls the candy until it returns to its original position and orientation. Given that AB=4AB = 4 and BD=CD=3BD =CD = 3, find the length of the path traced by AA.
Part 7
p19. In their science class, Adam, Chris, Eddie and Sam are independently and randomly assigned an integer grade between 7070 and 7979 inclusive. Given that they each have a distinct grade, what is the expected value of the maximum grade among their four grades?
p20. Let ABCDABCD be a regular tetrahedron with side length 22. Let point EE be the foot of the perpendicular from DD to the plane containing ABC\vartriangle ABC. There exist two distinct spheres ω1\omega_1 and ω2\omega_2, centered at points O1O_1 and O2O_2 respectively, such that both O1O_1 and O2O_2 lie on DE\overrightarrow{DE} and both spheres are tangent to all four of the planes ABCABC, BCDBCD, CDACDA, and DABDAB. Find the sum of the volumes of ω1\omega_1 and ω2\omega_2.
p21. Evaluate i=0j=0k=01(i+j+k+1)2i+j+k+1.\sum^{\infty}_{i=0}\sum^{\infty}_{j=0}\sum^{\infty}_{k=0} \frac{1}{(i + j +k +1)2^{i+j+k+1}}.
Part 8
p22. In ABC\vartriangle ABC, let IAI_A, IBI_B , and ICI_C denote the AA, BB, and CC-excenters, respectively. Given that AB=15AB = 15, BC=14BC = 14 and CA=13C A = 13, find [IAIBIC][ABC]\frac{[I_A I_B I_C ]}{[ABC]} .
p23. The polynomial x+2x2+3x3+4x4+5x5+6x6+5x7+4x8+3x9+2x10+x11x +2x^2 +3x^3 +4x^4 +5x^5 +6x^6 +5x^7 +4x^8 +3x^9 +2x^{10} +x^{11} has distinct complex roots z1,z2,...,znz_1, z_2, ..., z_n. Find k=1nR(z2n))+I(z2n),\sum^n_{k=1} |R(z^2n))|+|I(z^2n)|, where R(z)R(z) and I(z)I(z) indicate the real and imaginary parts of zz, respectively. Express your answer in simplest radical form.
p24. Given that sin33o+2sin161osin38o=sinno\sin 33^o +2\sin 161^o \cdot \sin 38^o = \sin n^o , compute the least positive integer value of nn.
Part 9
p25. Submit a prime between 22 and 20232023, inclusive. If you don’t, or if you submit the same number as another team’s submission, you will receive 00 points. Otherwise, your score will be min(30,4ln(x))\min \left(30, \lfloor 4 \cdot ln(x) \rfloor \right), where xx is the positive difference between your submission and the closest valid submission made by another team.
p26. Sam, Derek, Jacob, andMuztaba are eating a very large pizza with 20232023 slices. Due to dietary preferences, Sam will only eat an even number of slices, Derek will only eat a multiple of 33 slices, Jacob will only eat a multiple of 55 slices, andMuztaba will only eat a multiple of 77 slices. How many ways are there for Sam, Derek, Jacob, andMuztaba to eat the pizza, given that all slices are identical and order of slices eaten is irrelevant? If your answer is AA and the correct answer is CC, the number of points you receive will be: irrelevant? If your answer is AA and the correct answer is CC, the number of points you receive will be: max(0,30(12ACC))\max \left( 0, \left\lfloor 30 \left( 1-2\sqrt{\frac{|A-C|}{C}}\right)\right\rfloor \right)
p27. Let Ω(k) \Omega_(k) denote the number of perfect square divisors of kk. Compute k=110000Ω(k).\sum^{10000}_{k=1} \Omega_(k). If your answer is AA and the correct answer is CC, the number of points you recieve will be max(0,30(14ACC))\max \left( 0, \left\lfloor 30 \left( 1-4\sqrt{\frac{|A-C|}{C}}\right)\right\rfloor \right)
PS. You should use hide for answers. Rounds 1-5 have been posted [url=https://artofproblemsolving.com/community/c3h3267911p30056982]here. Collected [url=https://artofproblemsolving.com/community/c5h2760506p24143309]here.