A135089 → basis A007318

nonnegative coefficientsonly rational roots

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

Recurrence

\(\left(-1 + n\right)\,P_{n}(x) = \left(-2 - x + 2\,n + n x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)
\(P_{1}(x) = 10 + 5\,x\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
011
110515
22020545
34060305135
480160120405405
51604004002005051215
632096012008003006053645
7640224033602800140042070510935
812805120896089605600224056080532805
925601152023040268802016010080336072090598415
10512025600576007680067200403201680048009001005295245
1110240563201408002112002112001478407392026400660011001105885735
1220480122880337920563200633600506880295680126720396008800132012052657205
134096026624079872014643201830400164736010982405491202059205720011440156013057971615
148192057344018636803727360512512051251203843840219648096096032032080080145601820140523914845
Technical details
Node id
n-abd5c0abf48a5f04 · revision 0 · JSON
Definition source
derived:basis_map_A007318
Fingerprint
f6-11aec07ce60b6d61

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): yes
  • 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:   10,     5;
  2:   20,    20,     5;
  3:   40,    60,    30,     5;
  4:   80,   160,   120,    40,     5;
  5:  160,   400,   400,   200,    50,     5;
  6:  320,   960,  1200,   800,   300,    60,    5;
  7:  640,  2240,  3360,  2800,  1400,   420,   70,   5;
  8: 1280,  5120,  8960,  8960,  5600,  2240,  560,  80,  5;
  9: 2560, 11520, 23040, 26880, 20160, 10080, 3360, 720, 90, 5;
%F Formula
The row polynomials satisfy (n-1)*P(n,x) = (2*n-2+(n-1)*x)*P(n-1,x) for n >= 2, with P(0,x) = 1, P(1,x) = 10 + 5*x.
%t Mathematica
P[0, x_] := 1;
P[1, x_] := 10 + 5*x;
P[n_, x_] := P[n, x] = Expand[Together[((2*n - 2 + (n - 1)*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] = 1; v[2] = 10 + 5*x; for(n = 2, N, my(i = n + 1); v[i] = ((2*n - 2 + (n - 1)*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. [LW07] Lily L. Liu and Yi Wang. A unified approach to polynomial sequences with only real zeros. Advances in Applied Mathematics, 38(4):542–560, May 2007. doi:10.1016/j.aam.2006.02.003
  4. [SP14] J Schur and G Polya. Über zwei Arten von Faktorenfolgen in der Theorie der algebraischen Gleichungen. J. Reine Angew. Math., 1914.