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A081419
Largest value held in any register at the end of a halting computation by an n-instruction register Minski machine.
1
0, 1, 2, 3, 4, 6, 9, 34, 520
OFFSET
1,3
COMMENTS
We start with initially empty registers and include exactly one Halt instruction. Analogous to the Busy Beaver function, Sigma, for Turing Machines.
n<=5 are proved. 5<n<=9 are good lower bounds.
REFERENCES
Tibor Rado, On Noncomputable Functions, Bell System Technical Journal, vol. 41, # 3, 877-884, May 1963.
FORMULA
Noncomputable.
EXAMPLE
E.g. B(3) is of the form:
1: A+ -> 2
2: A+ -> 3
3: Halt
Halting with B(3)=2
CROSSREFS
Cf. A028444.
Sequence in context: A375621 A275173 A295394 * A108858 A294688 A094859
KEYWORD
hard,nice,nonn
AUTHOR
Rick J. Griffiths (rjg42(AT)cam.ac.uk), Apr 20 2003
STATUS
approved