OFFSET
1,1
COMMENTS
When a^7 + b^7 = m, (ma)^7 + (mb)^7 = m^8 is square.
When k in this sequence, k*(n^7) (n = 2, 3, ... ) is also in this sequence.
LINKS
Chai Wah Wu, Table of n, a(n) for n = 1..447
EXAMPLE
16^2 = 2^8 = 2^7 + 2^7, so 16 is in the sequence.
276922881^2 = 129^7 + 358^7, so 276922881 is in the sequence.
MATHEMATICA
lst={}; Do[If[IntegerQ[(n^2-a^7)^(1/7)], AppendTo[lst, n]], {n, 4*10^10}, {a, (n^2/2)^(1/7)}]; lst
CROSSREFS
KEYWORD
nonn
AUTHOR
XU Pingya, Sep 03 2017
STATUS
approved