|
Search: id:A127010
|
|
|
| A127010 |
|
a(0)=1. a(n) = the numerator of the sum of the reciprocals of the earlier terms of the sequence which are coprime to n. |
|
+0
2
|
|
| 1, 1, 2, 5, 11, 57, 126, 17609, 127439468, 344473534513077, 891027683693605833852, 156052046552117500148945259643265853536683707838813
(list; graph; listen)
|
|
|
OFFSET
|
0,3
|
|
|
LINKS
|
Leroy Quet, Home Page (listed in lieu of email address)
|
|
EXAMPLE
|
The sequence's terms, among terms a(0) through a(5), which are coprime to 6 are a(0)=1,a(1)=1,a(3)=5 and a(4)=11. So a(6) is the numerator of 1 +1 +1/5 +1/11 = 126/55, which is 126.
|
|
MATHEMATICA
|
f[l_List] := Sum[1/l[[k]], {k, Length[l]}]; g[l_List] := Block[{n = Length[l]}, Append[l, Numerator@f[Select[l, GCD[ #, n] == 1 &]]]]; Nest[g, {1}, 12] (*Chandler*)
|
|
CROSSREFS
|
Cf. A127009.
Sequence in context: A106887 A089609 A087185 this_sequence A131480 A018847 A134996
Adjacent sequences: A127007 A127008 A127009 this_sequence A127011 A127012 A127013
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Leroy Quet Jan 02 2007
|
|
EXTENSIONS
|
Extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), Jan 04 2007
|
|
|
Search completed in 0.002 seconds
|
