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Eight-bit strings starting with 1 or ending in 00

Question

Consider all strings of length 88 over the alphabet {0,1}\{0,1\}. How many of them have first character 11, or last two characters 0000, or both?

Short answer

160160. Inclusion–exclusion: 272^7 start with 11, 262^6 end with 0000, and 252^5 do both, so 128+64−32=160128+64-32=160.

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