basis-map coefficients of A030528, shifted → θ+1 → basis A013611

only rational roots

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

Recurrence

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

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
011
1-2-8-10
23244875
3-4-48-192-256-500
4580480128012803125
5-6-120-960-3840-7680-6144-18750
6716816808960268804300828672109375
7-8-224-2688-17920-71680-172032-229376-131072-625000
89288403232256161280516096103219211796485898243515625
9-10-360-5760-53760-322560-1290240-3440640-5898240-5898240-2621440-19531250
10114407920844805913602838528946176021626880324403202883584011534336107421875
11-12-528-10560-126720-1013760-5677056-22708224-64880640-129761280-173015040-138412032-50331648-585937500
121362413728183040164736010543104492011521686896644217241607497318408996782086543114242181038083173828125
13-14-728-17472-256256-2562560-18450432-98402304-393609216-1180827648-2624061440-4198498304-4580179968-3053453312-939524096-17089843750
1415840218403494403843840307507201845043208434483202952069120787218432015744368640229008998402290089984014092861440402653184091552734375
Technical details
Node id
n-d74992e60bc95ea4 · revision 0 · JSON
Definition source
derived:basis_map_A013611
Fingerprint
f6-03d7b8417365c509

Observed on the stored rows ?

  • Degrees: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 (affine: slope 1, intercept 0)
  • 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:   1;
  1:  -2,   -8;
  2:   3,   24,    48;
  3:  -4,  -48,  -192,   -256;
  4:   5,   80,   480,   1280,    1280;
  5:  -6, -120,  -960,  -3840,   -7680,    -6144;
  6:   7,  168,  1680,   8960,   26880,    43008,    28672;
  7:  -8, -224, -2688, -17920,  -71680,  -172032,  -229376,  -131072;
  8:   9,  288,  4032,  32256,  161280,   516096,  1032192,  1179648,   589824;
  9: -10, -360, -5760, -53760, -322560, -1290240, -3440640, -5898240, -5898240, -2621440;
%F Formula
The row polynomials satisfy n*P(n,x) = -(n+1+(4*n+4)*x)*P(n-1,x) for n >= 1, with P(0,x) = 1.
%t Mathematica
P[0, x_] := 1;
P[n_, x_] := P[n, x] = Expand[Together[(-(n + 1 + (4*n + 4)*x)*P[n - 1, x])/(n)]];
Table[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten
%o PARI/GP
P(N) = {my(v = vector(N + 1)); v[1] = 1; for(n = 1, N, my(i = n + 1); v[i] = (-(n + 1 + (4*n + 4)*x)*v[i - 1])/(n)); 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.