bio | website | math.mit.edu/~jblewis |
---|---|---|

location | Massachusetts | |

age | 30 | |

visits | member for | 4 years, 9 months |

seen | Jun 18 '12 at 19:10 | |

stats | profile views | 2,200 |

I am a graduate student at MIT. See my webpage for more information.

Sep 30 |
awarded | Explainer |

Mar 15 |
awarded | Yearling |

Jun 25 |
awarded | Excavator |

Mar 15 |
awarded | Yearling |

Dec 8 |
awarded | Popular Question |

Mar 15 |
awarded | Yearling |

Apr 5 |
comment |
probability that a random element of Z/NZ can be written as a subset sum of others
It seems to me like the question in the postscript asks for the probability that every element of $\mathbb{Z}/ N \mathbb{Z}$ can be written as a sum of some elements of $A$, whereas the original question asks for the probability that a particular element in $\mathbb{Z}/ N \mathbb{Z}$ can be written as a sum of some elements of $A$; which question are you really interested in? |

Apr 4 |
comment |
Finding cycle with constraints
It might be helpful if you described your algorithm for cycles of even length. Also, what is the motivation? |

Apr 4 |
comment |
Finding cycle with constraints
Please edit for typos and LaTeX. Such a cycle obviously need not exist -- what is the actual question you intend? Is this a homework assignment? |

Mar 24 |
comment |
volume of the projected body
What sort of answer are you looking for? |

Mar 24 |
comment |
Fun question in additive combinatorics
Yes, my mistake. |

Mar 24 |
comment |
Fun question in additive combinatorics
Is this a question to which you already know the answer? |

Mar 24 |
comment |
Maximal number of directed edges in suitable simple graphs on $n$ vertices without directed triangles.
gordon-royle, this is ruled out for $k \geq 2$ by the condition that there be no 2-cycles. |

Mar 22 |
comment |
Assigning positive edge weights to a graph so that the weight incident to each vertex is 1.
@Didier Piau, good question! |

Mar 22 |
comment |
A density on the natural numbers invariant with respect to the multiplication
Which is consistent with what I wrote: Gerald Edgar's density is the limit of a subsequence of the sequence whose limit is the usual density. |

Mar 22 |
revised |
Assigning positive edge weights to a graph so that the weight incident to each vertex is 1.
added 88 characters in body |

Mar 22 |
revised |
Assigning positive edge weights to a graph so that the weight incident to each vertex is 1.
added 222 characters in body |

Mar 22 |
comment |
Assigning positive edge weights to a graph so that the weight incident to each vertex is 1.
Yes, that's correct. I'll edit to make it clearer. |

Mar 22 |
comment |
A density on the natural numbers invariant with respect to the multiplication
(In fact, your proposed definition must agree with the usual one whenever the usual one exists.) |

Mar 22 |
comment |
A density on the natural numbers invariant with respect to the multiplication
Then all the positive integers have density 1, but the even integers still have density 1/2. Right? |