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help!!
Write explicit formulas for each of the following sequences:

1, 4, 9, 16, . . .

3, -1, -3, -5, . . .

1, 7, 25, 79, 241, . . .

Respuesta :

1.  this is a series of squares  Formula is an = n^2

2. Arithmetic series with common difference d = -2.

an = a1 + (n-1)d  = 3 -2(n-1)


Cant see the rule for Number 3