|
|
A165499
|
|
First term of maximal arithmetic progression with difference n, such that each term k has tau(k) = n.
|
|
4
|
|
|
|
OFFSET
|
1,2
|
|
COMMENTS
|
a(6) <= 161804009483982959337354063701 if A165498(6) = 9, and at least 1e14.
a(8) = 380017309607.
a(12) <= 11673662470957217427690002629075 if A165498(12) = 10, and at least 1e10.
a(16) = 2a(8).
A165498(n) = 1 for odd n, so a(7) = 64; a(9) = 36; a(11) = 1024; a(13) = 4096; a(15) = 144; etc.
|
|
LINKS
|
|
|
EXAMPLE
|
A165498(4) = 8, and exhaustive search finds tau(5989) = tau(5993) = tau(5997) = tau(6001) = tau(6005) = tau(6009) = tau(6013) = tau(6017) = 4 is the first example of an 8-term progression, so a(4) = 5989.
|
|
CROSSREFS
|
|
|
KEYWORD
|
hard,nonn,more
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|