Use each of the year's 4 digits exactly once, with standard math operations, to build every number from 1 to 100. Allowed: + − × ÷ ( ) ^ and decimals (e.g., .2), concatenation (e.g., 26), unary minus, factorial !, double factorial !!, and √. The classic family-break challenge.
Target: 1
Pick any number 1–100, then enter an expression that evaluates to it.
Rules in detail
Use every digit of the year exactly once. Order doesn't matter.
Concatenation counts: 26 uses one '2' and one '6'.
Decimals count: .2 uses one '2'. .02 uses one '0' and one '2'.