One more list with a few differences..... 4 tetra- 5 penta- 6 hexa- 7 hepta- 8 octa- 9 ennea- 10 deca- 11 hendeca- 12 dodeca- 13 trideca- 14 tetradeca- 15 pentadeca- 16 hexadeca- 17 heptadeca- 18 octadeca- 19 enneadeca- 20 icosi- 21 icosihena- 22 icosidi- 23 icositri- 24 icositetra- <A HREF="http://www.unc.edu/~rowlett/math111/Prefixes.PDF" target="_new">http://www.unc.edu/~rowlett/math111/Prefixes.PDF</A>