what are the three term of 2,8,26,80

2 answers

what are the three terms of 36,69,135,267
huh? You just listed 4 terms, so which three do you want?
the first sequence is just 3^n - 1
the second can be written as
2^5 + 4, 2^6 + 5, 2^7 + 7, 2^8 + 9
So I think you made a typo, and the 1st term should be 35. In that case, then nth term is 16*2^n + 2n+1