Because "interesting" is undefined and open-ended, this "mission" is not that difficult. The following is one way to solve it:
a. Go to Sloane's indispensable On-Line Encyclopaedia of Integer Sequences. http://www.research.att.com/~njas/sequences/ b. Enter the number n in the search box. c. You will get quite a few sequences containing n. Find an intersection in which n is the smallest element. For example, n=391. There are 922 hits. Consider the hits in order: - A078972 a semiprime whose prime factors have an equal number of decimal digits. - A078972 number of permutations satisfying i-2<=p(i)<=i+4 Already the intersection is just 6, 391,... - A133630 nonprime number k such that binomial(k+p,k) mod k=1 where p=1. 6 is not an element of this sequence (but 391 is). We have an an "interesting fact" about 391. ----- Original Message ----- From: Dan Bron <[email protected]> Date: Saturday, August 22, 2009 18:37 Subject: Re: [Jprogramming] Unforgettable times To: 'Programming forum' <[email protected]> > I wrote: > > http://www2.stetson.edu/~efriedma/numbers.html . > But 226 > > has lost its title. > > This page lists an interesting fact about each first 10,000 non- > negative numbers. So far, it can't find an > interesting fact > about any of these numbers: > > 391 424 460 508 514 534 549 557 611 622 > 647 655 674 685 698 702 706 723 725 754 > 758 759 761 772 774 776 779 790 796 807 > 811 817 824 826 828 830 837 838 845 860 > 865 871 886 890 893 908 915 921 928 931 > 932 937 938 944 947 954 962 965 970 971 > 978 980 > > So 391 now holds the title as the smallest uninteresting > number. Your mission, should you choose to accept it, is > to find a > reason 391 is interesting. Then 424. Then 460. Etc. ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
