Re: Conjecture:at least one prime p between (n-1)n/2 and n(n+1)/2
- To: mathgroup at smc.vnet.net
- Subject: [mg107137] Re: Conjecture:at least one prime p between (n-1)n/2 and n(n+1)/2
- From: a boy <a.dozy.boy at gmail.com>
- Date: Wed, 3 Feb 2010 06:13:50 -0500 (EST)
- References: <hk6d0n$m4h$1@smc.vnet.net>
Clear[n]; FindInstance[ NextPrime[n (n - 1)/2] > n (n + 1)/2 && 0 < n < 2^2^20, {n}, Integers] FindInstance::nsmet: The methods available to FindInstance are insufficient to find the requested instances or prove they do not exist. On Feb 1, 7:13 pm, a boy <a.dozy.... at gmail.com> wrote: > I have a Conjecture: For every n > 1 there is always at least one prime p > such that (n-1)n/2 < p < n(n+1)/2 > > n = 2; b = 1; > While[NextPrime[b] < (b = n (n + 1)/2), n++] > n > > $Aborted > > 14394105 > > In this diagram,there is at least one small point(prime) between every tw= o > medium points(triangle number ). > > In[58]:= start = 1; > n = 400; > pl = Table[{Prime[i], n}, {i, start, n}]; > tl = Table[{i (i + 1)/2, n}, {i, start, n}]; > ListLinePlot[Prime[Range[start, n]], > Epilog -> {PointSize[Medium], Point[tl], PointSize[Small], Point[pl]}] > > The still unsolved Legendre's conjecture asks whether for every n > 1, th= ere > is a prime p, such that n^2 < p < (n + 1)^2. Comparing, > > (n+1)^2-n^2=2n+1, while n(n+1)/2-(n-1)n/2=n