[seqfan] A014206 and computer algebra systems

[Thomas Baruchel]

Dear fellow seqfans,

just noticed that A014206 are the integers for which several tried CAS are able to
give explicit solutions for the equation ((x^2-n)^2-n)^2-n =x

Here is what I mean with Maxima:

(%i15) f(c) := solve( ((x^2-c)^2-c)^2-c =x, x)$
(%i16) for i:1 thru 128 do block([c:f(i)], if length(c) > 3 then print(i));
2
4
8
14
22
32
44
58
74
92
112

Maybe someone will understand why.

Best regards,

--
Thomas Baruchel