Looking for world capitals were all of their trigrams (three-letter sequences) don't appear in any other capital. e.g. if "Lisbon" were an answer, there would have to be NO other capital with "LIS", "ISB", "SBO", or "BON". Trigrams taken into account must be in the same word (not going over spaces or dashes, but apostrophes are fine). Capital names are based on the "Capitals of the world" quiz, but commonly-accepted alternate capitals or alternate spellings and whatever they affect are taken into account as bonuses.