Track / Stage 4 / 56 of 340 #316 of 1964

Problem 316

AMC 12 late, AIME early

Combinatorics Difficulty 4.7 Find the answer

$1.19 n+m$ 位由 $m$ 个 $0, n$ 个 1 组成的符号串, 其中 $n \leqslant m+1$ , 试问不存在两个 1 相邻的符号串的数目.

The source for this one didn't record the answer, so there is nothing to check what you type against. Work it on paper and mark yourself against the solution below.

Official solution

None

Source: NuminaMath-1.5, licensed Apache-2.0. Statement reproduced verbatim; metadata (topic, difficulty, ordering) added by this project.