Welcome to the parlour, where finite numbers dream. - up to [omega](Omega.md "Omega") and into the [attic](Lower_attic.md "Lower attic") - over to <a href="http://modelsofpa.info/" class="external text">Peano's Parlour</a>, the site for open problems in nonstandard models of Peano Arithmetic and related theories - [](Busy_beaver_function.md) values - [](Fast-growing_hierarchy.md) - [](Hardy_hierarchy.md) - [](Slow-growing_hierarchy.md) - [BEAF](BEAF.md "BEAF") arrays and [](Bird's_array_notation.md) - [](Ackermann_function.md) values - [](Graham's_number.md) - [](Knuth's_up-arrow_notation.md) - [](Googol.md#Googol_plex), [](Googol.md#Googol_bang), [](Googol.md#Googol_stack) and the [](Googol.md#The_googol_plex_bang_stack_hierarchy) - [googol](Googol.md "Googol") - 1 - [0](Zero.md "Zero")