Busy Beaver number $BB(1)$

OrdinaryArtery, via Wikimedia Commons. CC BY-SA 4.0.
The maximal number of steps that a $1$-state Turing machine can make on an initially blank tape before eventually halting.
Value: $1$
Updates
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Lower bound: $1$
Reference unknown
[via Sequence A060843 in the OEIS] -
Upper bound: $1$
Reference unknown
[via Sequence A060843 in the OEIS]