Sequence Riddle

[dolce]

Well, this sequence seemed easy at first, but I am bangin' my head against the wall after three hours of torture.

Given a sequence of numbersbr]
1/6, -1/6, 3/20, -2/15, 5/42, ...

I need to define the above sequence as a function of n, with n 0 -> infinity

Ai, my head is boiling!

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encyclopedia.thefreedictionary.com/sequence
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[Mikey // Neon]

1/6, -1/6, 3/20, -2/15, 5/42, ...

was quite easy

certain numbers added together equal the other numbers then you can use the un used number to ad into the other numbers.haha jk. The equation is rigged. FAKE. not possible:) You got set up

[dolce]

possible

1/6 = 1/(2*3)
-1/6 = -2/(3*4)
3/20 = 3/(4*5)
-2/15 = -4(5*6)
5/42 = 5/(6*7)

a_n = ((-1)^(n+1))*n/(n+1)(n+2)