PPL 154 / 177 permanent IDsPrize Problem Ledger · PPLChecked 2026.07.26
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Prize Problem LedgerIndependentPPL 154Shallit #4 · DFA versus NFA separation gap

Permanent problem IDPPL 154

Source-statedIndependentconjecture

Formal languages

Shallit #4 · DFA versus NFA separation gap

Find good bounds on the worst-case ratio between deterministic and nondeterministic state complexity for separating two words.

automata theorytheoretical computer scienceformal languages
01

The problem

Find good bounds on the worst-case ratio between deterministic and nondeterministic state complexity for separating two words.

Open since2014source-stated by 2014
Last checked2026.07.26Catalog verification
02

Reward offers

Offer 01£50Jeffrey Shallit
Personal offer

Personal cash offer stated in Shallit’s official talk. The live talks page records subsequent updates, including a paid solution to one omitted problem; confirm claim procedure with the sponsor before relying on the award.

Award source ↗Rules ↗
03

Sources & reading

2 unique reference linksSponsor’s official problem slides Claim or award rules
04

Related open targets

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