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Response Details:
No it is not zero. The number 19 is prime, so multiplying the first 18 integers together gives a number that is not a multiple of 19. Try to look at the pattern, you understand what factorial means, right?
1!=1, the remainder is 1
2!=2, the remainder is 2
3!=6, R=6
4!=24, R=5
5!=120, R=6
6!=720, R=17
7!=5040, R=5
NOW HERE IS THE BEAUIFUL PART>
IF the R=1, and you multiply by the next number to get the next factor, you can just multiply THE REMAINDER BY THE NEXT NUMBER...
SO if R=17, multiply R by 7 and get 119, the just find the remainder of 119/19 which is 5.
GET IT??? KEEP GOING...
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