A196347 → basis A013609 → D+1

nonnegative coefficientsonly rational roots

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

Recurrence

\(\left(x + n\right)\,P_{n}(x) = \left(2\,n + 4\,n x + 2\,n x^{2} + 2\,n^{2} + 2\,n^{2} x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)

Rows ?

nx0x1x2x3x4x5x6x7Pn(1)
011
1426
22432864
319243228848960
4192061446912307238418432
52304096000153600115200384003840430080
632256016588803456000368640020736005529604608011796480
75160960316108808128512011289600090316800406425609031680645120371589120
Technical details
Node id
n-3d8375aa67491629 · revision 0 · JSON
Definition source
derived:one_plus_derivative
Fingerprint
f6-e99c3824c4864868

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:          4,           2;
  2:         24,          32,           8;
  3:        192,         432,         288,           48;
  4:       1920,        6144,        6912,         3072,          384;
  5:      23040,       96000,      153600,       115200,        38400,         3840;
  6:     322560,     1658880,     3456000,      3686400,      2073600,       552960,       46080;
  7:    5160960,    31610880,    81285120,    112896000,     90316800,     40642560,     9031680,      645120;
  8:   92897280,   660602880,  2023096320,   3468165120,   3612672000,   2312110080,   867041280,   165150720,   10321920;
  9: 1857945600, 15049359360, 53508833280, 109247201280, 140460687360, 117050572800, 62426972160, 20065812480, 3344302080, 185794560;
%F Formula
The row polynomials satisfy (n+x)*P(n,x) = (2*n^2+2*n+(2*n^2+4*n)*x+2*n*x^2)*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[((2*n^2 + 2*n + (2*n^2 + 4*n)*x + 2*n*x^2)*P[n - 1, x])/(n + x)]];
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] = ((2*n^2 + 2*n + (2*n^2 + 4*n)*x + 2*n*x^2)*v[i - 1])/(n + x)); 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.