Write an expression for the apparent nth term aₙ of the sequence. (Assume that n begins with 1.) 6, 3, 7, 11, 8, 15, 9, 19, 10, ...
a) aₙ=2n+4
b) aₙ=2n+2
c) aₙ=4n−2
d) aₙ=3n+3