Patrick Crotty
p...@physics.wm.edu
>Some said that this is the sequence
>1!!!, 2!!!, 3!!!, and that the next entry would be 4!!!. But
Make that 1!!, 2!!, 3!! (3! = 6, 6! = 720; of course for 1 and 2 the number
of !'s doesn't make any difference)
>what about 0? I've always seen 0! defined as 1, not 0, and so
That's what bothered me, too
>unless I'm completely missing something, the original puzzle
>should have been called 1, 1, 2, 720!. It seems to me that
>a more correct solution, if 0 is to be included, would be
>0, 1!, 2!!, 3!!!, and so the next entry would be 4!!!!, not 4!!!.
No. See above, 3!!! = 720! (a number I am not going to compute).
^this is a mathematical '!', not a punctuation mark
Still puzzled. What did we miss?
>>Some said that this is the sequence
>>1!!!, 2!!!, 3!!!, and that the next entry would be 4!!!. But
>Make that 1!!, 2!!, 3!! (3! = 6, 6! = 720; of course for 1 and 2 the number
>of !'s doesn't make any difference)
No, you _want_ 720!.
>>what about 0? I've always seen 0! defined as 1, not 0, and so
>That's what bothered me, too
>>unless I'm completely missing something, the original puzzle
>>should have been called 1, 1, 2, 720!. It seems to me that
>>a more correct solution, if 0 is to be included, would be
>>0, 1!, 2!!, 3!!!, and so the next entry would be 4!!!!, not 4!!!.
>No. See above, 3!!! = 720! (a number I am not going to compute).
> ^this is a mathematical '!', not a punctuation mark
>Still puzzled. What did we miss?
The last character in the Subject: header?
Seth
See above indeed. I see 720! following 2 in the sequence. I do not
see 3!! = 720 in the sequence.
In any case, 0!! = 1, so where did the initial 0 come from? It's the
initial 0 that causes people to guess 0, 1!, 2!!, 3!!!, 4!!!! rather
than any of the sequences with a constant number of apllications of
factorial.
-- David A. Karr (ka...@cs.cornell.edu)
Another reasonable possibility for the next number is (720!+1)!!!
--
Dave Ring
dwr...@tam2000.tamu.edu
or perhaps its generated recursively from
x -> (x+1)!!
or, depending on how you interpret the ! in the sequence
x -> (x+1)!!!
so the next number is 721!! or (720!+1)!!!