# Confluent hyper-geometric function

Is there any identity in the confluent hypergeometric function that connects the following?
$${}_1{F_1}left( {a + n + 1,b + n + 1, – c} right)$$ and
$${}_1{F_1}left( {a + 1,b + 1, – c} right)$$ where a, b and c are positive real numbers