OFFSET
0,2
COMMENTS
Note that g_k(x,y) always has positive coefficients. The sequence are degrees for which a certain construction (see paper by D'Angelo-Lebl) of proper monomial holomorphic mappings of balls does not give new noninvariant monomial mappings.
It is unknown if this sequence is infinite (conjectured to be so). Furthermore A143106 is definitely a subsequence of this sequence, but it is unknown if the two are in fact equal.
REFERENCES
J. P. D'Angelo, Simon Kos and Emily Riehl. A sharp bound for the degree of proper monomial mappings between balls. J. Geom. Anal., 13(4) (2003) 581-593.
LINKS
J. P. D'Angelo and J. Lebl. Complexity results for CR mappings between spheres, arXiv:0708.3232, Internat. J. Math. 20 (2) (2009) 149
J. Lebl and D. Lichtblau, Uniqueness of certain polynomials constant on a hyperplane, arXiv:0808.0284 (2008).
EXAMPLE
For example when d=7, we get the following new polynomials x^7 + 7/2 xy + 7/2 x^5y 7/2 xy^5 and x^7 + 7 x^3y + 7 xy^3 + 7 x^3y^3. Hence 7 is not in the sequence.
MATHEMATICA
See the paper by Lebl-Lichtblau
CROSSREFS
KEYWORD
nonn
AUTHOR
Jiri Lebl (jlebl(AT)math.uiuc.edu), Jul 25 2008
STATUS
approved