ok, so IDK why my answer was deleted even though it was correct but here goes. it would be nice if you comment to ask me to fix what's wrong instead of just deleting the answer
1st odd number is 1
2nd odd number is 3
3rd odd number is 5
it seems like the mod did not like my method so we will try to find an aritmetic sequence since each term increases by the same amount
the formula for an aritmetic sequence is [tex]a_n=a_1+d(n-1)[/tex] where
[tex]a_n[/tex] is the nth term (you can also write f(n) if you need a function)
[tex]a_1[/tex] is the first term
d is the common differnce or how much each term increases by ([tex]d=a_n-a_{n-1}[/tex])
n is the counter to tell us what term we are on
so
1st term is 1 so [tex]a_1=1[/tex]
each term increases by 5-3=2 and 3-1=2, by 2, so d=2
therefore, [tex]a_n=1+2(n-1)[/tex]
the 137th term would be [tex]a_{137}=1+2(137-1)[/tex]
[tex]a_{137}=1+2(136)[/tex]
[tex]a_{137}=1+272[/tex]
[tex]a_{137}=273[/tex]
the 137th odd number is 273
