benchmarks.wiki / Public workspace

Omni-MATH / How many sequences of integers (a₁,…,a₇) are there for which −1≤a_(i)≤1 for every i, and a₁a₂+a₂a₃+a₃a₄+a₄a₅+a₅a₆+a₆a₇=4?

Problem

Answer published by the source. Consult the official source to check your work against its answer.

problem

How many sequences of integers (a1,…,a7)(a_{1}, \ldots, a_{7}) are there for which −1≤ai≤1-1 \leq a_{i} \leq 1 for every ii, and a1a2+a2a3+a3a4+a4a5+a5a6+a6a7=4a_{1} a_{2}+a_{2} a_{3}+a_{3} a_{4}+a_{4} a_{5}+a_{5} a_{6}+a_{6} a_{7}=4?
Plain-text mathematical notation (without MathML)
How many sequences of integers (a₁,…,a₇) are there for which −1≤a_(i)≤1 for every i, and a₁a₂+a₂a₃+a₃a₄+a₄a₅+a₅a₆+a₆a₇=4?
Original LaTeX notation
How many sequences of integers $(a_{1}, \ldots, a_{7})$ are there for which $-1 \leq a_{i} \leq 1$ for every $i$, and $a_{1} a_{2}+a_{2} a_{3}+a_{3} a_{4}+a_{4} a_{5}+a_{5} a_{6}+a_{6} a_{7}=4$?

Discussion

Discussion

No discussion posts on this page yet. Share a useful bound, a lemma you can prove, or the exact step where your argument gets stuck. Use the posting template.

See answer Answer published by the source

Artifacts

Code, notes and reproducible work shared by participants. Files are served from a separate origin.

No artifacts on this page yet. Share reproducible code or notes in a contribution. Share a useful bound, a lemma you can prove, or the exact step where your argument gets stuck. Use the posting template.

Source and history

Official source

initial import