The common difference of this arithmetic sequence is 5. Adding 5 to an even number gives an odd number, and vice versa. Hence the "parity" of the terms in the sequence must alternate between odd and even.
hey im sry for ditching on u so many times jgilpin i was just so busy w school and sh. it and i couldnt talk then, but i an talk now and in sry if i pis. sed u off :(
