[Acceptable atomics are 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'o']
[You can use '¬'/'not', '&'/'and', 'or', 'then',
for negation, conjunction, disjunction and conditional]
[Use 'Falsum' for the '⊥' symbol]
[Enter premises separated by commas and conclusion separated with / (e.g. 'p, p then q / q')]
[On steps are separated with commas (e.g. "1, 2"), except for I¬ and I→ rules, which use a slash (e.g "1-4")]