SOLUTION: Find the units digit of the sum,$$ 1! + 2! + 3! + \cdots + 2006!. $$(latex)
Find the units digit of the sum, 1! + 2! + 3! + ... + 2006!.(not latex)
I am stuck. I cannot find a pa
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Exponential-and-logarithmic-functions
-> SOLUTION: Find the units digit of the sum,$$ 1! + 2! + 3! + \cdots + 2006!. $$(latex)
Find the units digit of the sum, 1! + 2! + 3! + ... + 2006!.(not latex)
I am stuck. I cannot find a pa
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Question 1169664: Find the units digit of the sum,$$ 1! + 2! + 3! + \cdots + 2006!. $$(latex)
Find the units digit of the sum, 1! + 2! + 3! + ... + 2006!.(not latex)
I am stuck. I cannot find a pattern because of the high numbers that this problem goes to. I have spent a lot of time, but haven't got anything. Thank you. Answer by ikleyn(52813) (Show Source):
From the first glance, the problem seems to be hard, but . . . actually . . . it is a joke problem.
As soon as the last digit of n! is zero, it does not influence more on the last digit of the sum . . .
So, the last requested digit comes from
1! + 2! + 3! + 4! + 5! = 1 + 2 + 6 + 24 + 120
and is, T H E R E F O R E, 3.
ANSWER. The last digit of 1! + 2! + 3! + . . . + 2006! is .
