This paper deals with the
number pn(A) of essentially n-ary polynomials of an idempotent universal algebra A.
Under the condition that there is a commutative binary polynomial ⋅ it is proved that
pn+1(A) ≧ pn(A) + (n− 1), provided pn(A)≠1. If ⋅ is also associative this inequality
is improved to