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| Here is the reference. Unfortunately it only mentions the problem casually and moves on to other rather theoretical things ... apart from that I have no other reference. Approximate counting. D. Welsh . Surveys in Combinatorics, 1997. R. A.... |
| In any sequence of ten distinct real numbers, there exists an increasing subsequence of four terms or a decreasing subsequence of four terms. This assertion is an instance of the Erd?s -Szekeres theorem, (1913-1996) and (1911-2005) resp. For... |
| Did you know the following avatar of Pythagoras theorem?. Consider a right-angled triangle of catheti (Greek work plural of cathetus, meaning each of the sides forming the vertex with the right angle) of lengths a and b. Let h be the length of the... |
| In order to contextualize the question, let us first examine some examples. Function Nest is useful to generate the multiple compositions of a given function: [mcode] NestList[f, x, 5] {x, f[x], f[f[x]], f[f[f[x]]], f[f[f[f[x]]]],... |
| Look at this picture of a semi-circular fan spanning 120 degrees having a variety of internal tangential circles. Now, ponder the following... |
| Consider the following triangulated planar object We notice that it has 10 triangular faces.In general, given a planar graph, how can we obtain... |
| In the process of developing some demonstrations I published recently about bisecting the perimeter of triangles I came across the following result. Consider the... |
| In looking for something entirely different I came across the following problem : The product of the ages of David' s children is the square of the sum of their ages. David has less than eight children. None of his children have the same age. None... |