SerialHunt

Fancy serials

17 patterns, counted exactly

Each definition is strict, and each count comes from checking all 100,000,000 possible eight-digit serials, not from folklore. The counts do not overlap: a solid is not also counted as a radar.

PatternExampleDefinitionSerialsOdds
Ladder 123 45678 The digits run straight up or straight down, one step at a time. 6 1 in 16,666,666
Solid 777 77777 Every one of the eight digits is the same. 10 1 in 10,000,000
Very low serial 000 00007 Numbered 1 to 10: one of the first ten notes in its run. 10 1 in 10,000,000
Super radar 811 11118 A radar whose six middle digits are all identical. 90 1 in 1,111,111
Super repeater 121 21212 A two-digit pair repeated four times over. 90 1 in 1,111,111
Double quad 111 12222 Four of one digit, then four of another. 90 1 in 1,111,111
Low serial 000 00047 Numbered 11 to 100: within the first hundred of its run. 90 1 in 1,111,111
High serial 999 99987 Numbered 99,999,900 or above: one of the last hundred in its block. 100 1 in 1,000,000
Near solid 177 77777 Seven digits are the same, and the odd one out sits at one end. 180 1 in 555,555
True binary 100 11010 Written with nothing but zeros and ones. 254 1 in 393,700
Seven of a kind 771 77777 Seven of the eight digits are the same, the odd one somewhere in the middle. 540 1 in 185,185
Partial ladder 123 45699 Six or seven digits in a row run consecutively up or down. 2,834 1 in 35,285
Radar 123 44321 The serial reads the same backwards as forwards. 9,900 1 in 10,101
Repeater 123 41234 The first four digits repeat exactly as the last four. 9,900 1 in 10,101
Binary 474 74774 Only two different digits appear in the whole serial. 11,176 1 in 8,947
Birthday 070 41776 Reads as a real calendar date in MM-DD-YYYY form, years 1700 to 2100. 146,766 1 in 681
Trinary 123 21233 Only three different digits appear in the whole serial. 695,520 1 in 143

Rarer than 1 in 5,000 is worth keeping on its own. A pattern on a star note, or on a low-numbered note, stacks.