What's the formula for the sequence 3 6 8 16 18 36 38 76

3 6 8 16 18 36 38 76


n 1 = a
n 2 = 2 n 1
n 3 = n 2 +2
n 4 = 2 n 3
n 5 = n 4 +2
n 6 = 2 n 5
n 7 = n 6 +2
n 8 = 2 n 7

all odd place terms are two more than their previous terms

all even places have terms that are double that of their previous terms.

so, the formula can be two folds.

so,

if n is the place of term in sequence &

if x is the value of the term

then

x = (n+1)/2 ; if n is odd [other than 1]

x = 2 (n-1) : if n is even

x = 3 ; if n = 1.

yeah right. had you done so, at least i would not have submitted my answer. its not up to that standard.

sorry, buddy. just wanted to help.

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First number is multiplied by 2. Second number gets 2 added to it. Third number gets multiplied by 2. Fourth number gets 2 added to it. And so on.

x 2, then + 2, repeatedly

3 x 2 = 6
6 + 2 = 8
8 x 2 = 16
16 + 2 = 18
18 x 2 = 36
36 + 2 = 38
38 x 2 = 76
76 ....
78