A128112 - OEIS

%I #2 Jun 29 2008 03:00:00

%S 0,0,0,1,1,1,3,3,3,4,3,10,5,7,6,7,4,11,8,12,9,8,6,16,11,13,10,14,9,10,

%T 14,19,15,13,10,19,12,11,18,21,12,16,20,20,21,16,12,26,23,14,21,25,16,

%U 22,26,21,20,20,18,33,29,18,30,35,18,27,24,23,33,26,22,28,35,20,36,42

%N Number of uniform polyhedra with n faces.

%H Hart, George W., <a href="http://www.georgehart.com/virtual-polyhedra/uniform-info.html">Uniform Polyhedra</a>.

%H Maeder, Roman E., <a href="http://www.mathconsult.ch/showroom/unipoly/unipoly.html">Uniform Polyhedra</a>.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/UniformPolyhedron.html">Uniform Polyhedron.</a>

%F After 124th term, a(n) equals A055684(n-2) + 1 for n odd and A055684(n-2) + A055684(n/2-1) + A128115(n/2-1) + 2 for n even.

%e a(20)=12 because there are the icosahedron, the small cubicuboctahedron, the great cubicuboctahedron, the cubitruncated cuboctahedron, the great icosahedron, the octadecagonal prism, two octadecagrammic (18/5 and 18/7) prisms, the enneagonal antiprism, two enneagrammic (9/2 and 9/4) antiprisms and the enneagrammic crossed antiprism.

%Y Cf. A128113, A128114.

%K nonn

%O 1,7

%A Paulo de A. Sachs (sachs6(AT)yahoo.de), Feb 15 2007, corrected Feb 15 2007