[seqfan] Record values of sigma(n+1)/sigma(n)

zak seidov zakseidov at yahoo.com
Mon Oct 4 08:59:00 CEST 2010


%N A1 Integers n with record values of 
d(n) = sigma(n+1)/sigma(n).

 n,    d(n)
1,     3
179,  91/30,
239,  31/10,
359,  13/4,
719,  403/120,
839,  24/7,
1259,  52/15,
3359,  18/5,
5039,  403/105,
10079,  39/10,
25199,  12493/3192,
27719,  520/131,
50399,  8463/2125,
55439,  1612/385,
110879,  234/55,
166319,  992/231,
360359,  65520/15109,
665279,  1016/231,
831599,  15376/3465,
1081079,  640/143,
1441439,  252/55,
2162159,  20832/4511,
3603599,  699608/150335,
4324319,  1008/215,
12972959,  308/65,
21621599,  62496/12877,
43243199,  440944/90423,
61261199,  23064/4675,
73513439,  37632/7571,
122522399,  12796056/2553035,
205405199,  615040/122293,
245044799,  12897612/2559509,
410810399,  13888/2717,
698377679,  238080/46189,
735134399,  62992/12155

The last value of d(n)=
 62992/12155=
5.182394076511723570547099959

1. More terms?
2. Can we reach, say, d>6?
3. Is any limit for d(n) with n--> inf?

Thanks,
Zak


      




More information about the SeqFan mailing list