basis-map coefficients of A030528, shifted → D → basis A013611

only rational roots

Proved for all n all roots real, in (−∞, 0]coefficients of one signHadamard kernelinterlacing (weak)

Recurrence

\(\left(-1 + n\right)\,P_{n}(x) = \left(-n - 4\,n x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 0\)
\(P_{1}(x) = -1\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13Pn(1)
00
1-1-1
22810
3-3-24-48-75
4448192256500
5-5-80-480-1280-1280-3125
6612096038407680614418750
7-7-168-1680-8960-26880-43008-28672-109375
8822426881792071680172032229376131072625000
9-9-288-4032-32256-161280-516096-1032192-1179648-589824-3515625
10103605760537603225601290240344064058982405898240262144019531250
11-11-440-7920-84480-591360-2838528-9461760-21626880-32440320-28835840-11534336-107421875
12125281056012672010137605677056227082246488064012976128017301504013841203250331648585937500
13-13-624-13728-183040-1647360-10543104-49201152-168689664-421724160-749731840-899678208-654311424-218103808-3173828125
141472817472256256256256018450432984023043936092161180827648262406144041984983044580179968305345331293952409617089843750
Technical details
Node id
n-06c71d519c191976 · revision 0 · JSON
Definition source
derived:basis_map_A013611
Fingerprint
f6-03d7b8417365c509

Observed on the stored rows ?

  • Degrees: -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 (affine: slope 1, intercept -1)
  • Palindromic rows: no
  • γ-positive (gamma_positive): no
  • Nonnegative coefficients (nonn): no
  • Only rational roots (rr_by_factors: every nonzero row is a product of linear factors over ℚ): yes

Matches ?

No OEIS matches.

Submission text ?

Atlas rows n = 0, …, ascending powers of x
%e Example
Triangle begins:
  0:  0;
  1: -1;
  2:  2,    8;
  3: -3,  -24,   -48;
  4:  4,   48,   192,    256;
  5: -5,  -80,  -480,  -1280,   -1280;
  6:  6,  120,   960,   3840,    7680,    6144;
  7: -7, -168, -1680,  -8960,  -26880,  -43008,   -28672;
  8:  8,  224,  2688,  17920,   71680,  172032,   229376,   131072;
  9: -9, -288, -4032, -32256, -161280, -516096, -1032192, -1179648, -589824;
%F Formula
The row polynomials satisfy (n-1)*P(n,x) = -(n+4*n*x)*P(n-1,x) for n >= 2, with P(0,x) = 0, P(1,x) = -1.
%t Mathematica
P[0, x_] := 0;
P[1, x_] := -1;
P[n_, x_] := P[n, x] = Expand[Together[(-(n + 4*n*x)*P[n - 1, x])/(n - 1)]];
Table[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten
%o PARI/GP
P(N) = {my(v = vector(N + 1)); v[1] = 0; v[2] = -1; for(n = 2, N, my(i = n + 1); v[i] = (-(n + 4*n*x)*v[i - 1])/(n - 1)); v};
row(n, p) = {my(c = Vecrev(p)); c};
T(N) = {my(v = P(N)); concat(vector(#v, i, row(i - 1, v[i])))};
T(9)

polytool c48629374597

Properties

Proof chains ? JSON

Same fingerprint ?

References

  1. [Bra06] Petter Brändén. On linear transformations preserving the Pólya frequency property. Transactions of the American Mathematical Society, 358(8):3697–3716, February 2006. doi:10.1090/s0002-9947-06-03856-6
  2. [Bra15] Petter Brändén. Unimodality, log-concavity, real-rootedness and beyond. Handbook of enumerative combinatorics, :437–483, March 2015. doi:10.1201/b18255-10
  3. [SP14] J Schur and G Polya. Über zwei Arten von Faktorenfolgen in der Theorie der algebraischen Gleichungen. J. Reine Angew. Math., 1914.