olymmath

HMMT 2018 A8

  • Algebra and Number Theory
  • Answer

For how many pairs of sequences of nonnegative integers (b1,b2,…,b2018)\left(b_{1}, b_{2}, \ldots, b_{2018}\right) and (c1,c2,…,c2018)\left(c_{1}, c_{2}, \ldots, c_{2018}\right) does there exist a sequence of nonnegative integers (a0,…,a2018)\left(a_{0}, \ldots, a_{2018}\right) with the following properties:

  • For 0≤i≤2018,ai<220180 \leq i \leq 2018, a_{i}<2^{2018};
  • For 1≤i≤2018,bi=ai−1+ai1 \leq i \leq 2018, b_{i}=a_{i-1}+a_{i} and ci=ai−1∣aic_{i}=a_{i-1} \mid a_{i}; where ∣\mid denotes the bitwise or operation? (The bitwise or of two nonnegative integers x=⋯x3x2x1x0x=\cdots x_{3} x_{2} x_{1} x_{0} and y=⋯y3y2y1y0y=\cdots y_{3} y_{2} y_{1} y_{0} expressed in binary is defined as x∣y=⋯z3z2z1z0x \mid y=\cdots z_{3} z_{2} z_{1} z_{0}, where zi=1z_{i}=1 if at least one of xix_{i} and yiy_{i} is 1 , and 0 otherwise.)

Dataset text NuminaMath olympiads. Quoted with source.

Show the answer

\left(2^{2019}-1\right)^{2018}

Solutions

No solution is on olymmath yet. Official and human solutions come first when they arrive. AI solutions come after them, with a label.

Add a solution

Similar problems

These problems have the most words in common with this statement.

Locator hmmt/2018/a8 · Tag D8M5E2PPXM · Edit this page on GitHub · Keys: j next, k previous