olymmath

HMMT 2019 A10

  • Algebra and Number Theory
  • Answer

The sequence of integers {ai}i=0∞\left\{a_{i}\right\}_{i=0}^{\infty} satisfies a0=3,a1=4a_{0}=3, a_{1}=4, and

an+2=an+1an+⌈an+12−1an2−1⌉a_{n+2}=a_{n+1} a_{n}+\left\lceil\sqrt{a_{n+1}^{2}-1} \sqrt{a_{n}^{2}-1}\right\rceil

for n≥0n \geq 0. Evaluate the sum

∑n=0∞(an+3an+2−an+2an+an+1an+3−anan+1).\sum_{n=0}^{\infty}\left(\frac{a_{n+3}}{a_{n+2}}-\frac{a_{n+2}}{a_{n}}+\frac{a_{n+1}}{a_{n+3}}-\frac{a_{n}}{a_{n+1}}\right) .

Dataset text NuminaMath olympiads. Quoted with source.

Show the answer

\frac{14}{69}

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/2019/a10 · Tag 99KDGRCRVH · Edit this page on GitHub · Keys: j next, k previous