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K-theoretic Thom polynomials of contact singularities of relative dimension 1, in Grothendieck expansions

(Hierarchy of these singularities)


codimension 0

Local algebra C
Thom-Boardman class \Sigma^0
Codimension 0
K-Thom polynomial in Grothendieck expansion g_{}=1
Remarks This contact singularity is open in its Thom-Boardman class.
Source: Implicit function theorem.

codimension 1

Local algebra C[x]/(x^2)
Thom-Boardman class \Sigma^{1,0}
Codimension 1
K-Thom polynomial in Grothendieck expansion g_{1}
Remarks This contact singularity is open in its Thom-Boardman class.

codimension 2

Local algebra C[x]/(x^3)
Thom-Boardman class \Sigma^{1,1,0}
Codimension 2
K-Thom polynomial in Grothendieck expansion g_{1,1}+ 2g_{2} – ( 2g_{2,1}+g_{3} ) + g_{3,1}
Remarks This contact singularity is open in its Thom-Boardman class.

codimension 3

Local algebra C[x]/(x^4)
Thom-Boardman class \Sigma^{1,1,1,0}
Codimension 3
K-Thom polynomial in Grothendieck expansion g_{1,1,1}+ 5g_{2,1}+ 6g_{3}
– ( 5g_{2, 1, 1} + 16g_{3, 1}+ 9g_{4} )
+ ( 10g_{3, 1, 1} + 19g_{4, 1} + 5g_{5} )
– ( 10g_{4, 1, 1} +10g_{5, 1} + g_{6} )
+ g_{6, 1, 1}
– 4g_{2, 2}
+ ( 4g_{2, 2, 1} + 10g_{3, 2} )
– ( 10g_{3, 2, 1} + 10g_{4, 2} )
+ ( 10g_{4, 2, 1} + 5g_{5, 2} )
– ( 5g_{5, 2, 1} + g_{6, 2} )
+ g_{6, 2, 1}
Remarks This contact singularity is open in its Thom-Boardman class.

codimension 4

Local algebra C[x]/(x^5)
Thom-Boardman class \Sigma^{1,1,1,1,0}
Codimension 4
K-Thom polynomial in Grothendieck expansion ?
Remarks This contact singularity is open in its Thom-Boardman class.
Local algebra C[x,y]/(x^2,y^2)
Thom-Boardman class \Sigma^{2,0}
Codimension 4
K-Thom polynomial in Grothendieck expansion g_{2,2}
Remarks This contact singularity is open in its Thom-Boardman class.

codimension 5

Local algebra C[x]/(x^6)
Thom-Boardman class \Sigma^{1,1,1,1,1,0}
Codimension 5
K-Thom polynomial in Grothendieck expansion ?
Remarks This contact singularity is open in its Thom-Boardman class.
Local algebra C[x,y]/(xy,x^2+y^3)
Thom-Boardman class \Sigma^{2,0}
Codimension 5
K-Thom polynomial in Grothendieck expansion 2g_{2,2,1} + 4g_{3,2}
– ( g_{2, 2, 2} + 5g_{3, 2, 1} + 4g_{4,2} )
+ ( g_{3,2,2} + 4g_{4,2,1} + g_{5, 2} )
– g_{5,2,1}