The status of further terms is:
15 integral solutions: unknown
16 integral solutions: 503
17 integral solutions: unknown
18 integral solutions: 431
19 integral solutions: unknown
20 integral solutions: 2351
21 integral solutions: unknown
22 integral solutions: 3807
For least positive k such that equation y^2 = x^3 + k has exactly n integral solutions, see A179162.
If n is odd, then a(n) is perfect cube. [Ray Chandler]
About those unknown terms:
a(15) <= 2600^3 = (26* 10^2)^3
a(17) <= 10400^3 = (26* 20^2)^3
a(19) <= 93600^3 = (26* 60^2)^3
a(21) <= 4586400^3 = (26*420^2)^3
The term a(13) = 71991296 = 416^3 = (26*4^2)^3. (End)
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