Straight
The poker hand, hiding inside your digits.
The digit string contains five or more consecutive digits each exactly +1 (…12345… and its shifts), like 56789, 123456 or 801234. The term is borrowed from poker.
Your record
Raising the bar from three in a row to five collapses the count: only 105 in the whole range. A five-digit Straight has nowhere to hide — the entire string must be one of 12345, 23456, 34567, 45678, 56789, exactly 5 numbers; six-digit Straights number 100, with the run parked at the front, the back, or straddling the middle.
Why so rare: a five-step consecutive nail driven into a six-digit string leaves almost no freedom — the run's starting digit has only a handful of options, its position only two, and just one leftover digit plays freely.
Two pieces of trivia: the 1,000,000 cap means the perfect seven-digit straight 1234567 can never be rolled; and the Straight only honors ascents — a five-step fall like 98765 belongs to Descending Run instead. Poker players, note: no wraparound Broadway 10-J-Q-K-A here.