Every even integer from 40 onwards can be expressed as the sum of two odd composite numbers.
Proof
We can write all the even integers in one of the forms
\[10k, \; 10k+2, \; 10k+4, \; 10k+6, \; 10k+8\]
. We can write each of these as the sum of two composite numbers\[10k=15+(10k-15)\]
\[10k+2=27+(10k-25)\]
\[10k+4=9+(10k-5)\]
\[10k+6=21+(10k-15)\]
\[10k+8=33+(10k-25)\]
Take
\[k \ge 4\]
then each term is composite.