Proof step

Ray basis map theorem

Image under a basis map u^k -> P_k A008277

Concludes
basis_map_A008277 of basis_map_A007318 of Triangle T(n,k) giving number of degree-2n permutations which decompose into exactly k cycles of even length, k=0..n.
Premises
Theorem
[MW08, Thm 2] polytool RealRooted rayBasisMap_maps_realRootedIn_iff ?
Checked
polytool replayed · Lean not attempted
Technical details
Step id
e-87dc5132438f4e40 · JSON
Operation
Image under a basis map u^k -> P_k
{
  "map": "A008277",
  "operation": "basis_map"
}
Claims
{
  "claim": "real_rooted",
  "from_index": 0,
  "region": {
    "upper": {
      "closed": true,
      "value": "0"
    }
  }
}
Certificate
basis_map, SHA-256 d491ed92aaa0dce6e51cd7590e7d091d4d3047eda239553318a17d4bbf5f6110, 9,160 bytes (1,971 compressed); download
polytool replayed the certificate when the step was written.
Cited by

References

  1. [MW08] Shi-Mei Ma and Yi Wang. q-Eulerian polynomials and polynomials with only real zeros. The Electronic Journal of Combinatorics, 15(1):Research Paper 17, January 2008. doi:10.37236/741