Question

What is the pattern for 2,6,4,12,10,30,28

Answer 1

looks like a combination recursion
let term(n) be the nth term,

term(1) = 2
if n is odd: term(n) = 3term(n-1)
if n is even: term(n)= term(n-1) - 2

so the next terms are:
26, 78, 76, 228, 226, 678 .....

Answer 2

I don't know it always works