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Bn=1(1!)+2(2!)+...n(n!).
B(n) = (n+1)! - 1.
Can be proven by induction.
Why did the vector cross the road?
It wanted to be normal.
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Are you sure because it works for n=1 but not n>2
n=2
B(n) = 1(1!) + 2(2!) = 1+4 = 5
(2+1)! - 1 = 6 - 1 = 5
n=3
B(n) = 1(1!) + 2(2!) + 3(3!) = 1+4+18 = 23
(3+1)! - 1 = 24 - 1 = 23
...
Looks like it works to me.
Why did the vector cross the road?
It wanted to be normal.
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Your right. My fault. lol
mathsy, i just wonder, how did you get to the formula in the first place? just guessing?
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Pretty much.
I just wrote down B(n) for the first few n and looked for a pattern. Then once I found something that looked like it worked, I checked it using induction.
Why did the vector cross the road?
It wanted to be normal.
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