basis-map coefficients of A030528, shifted → basis A013610 → basis A013610

only rational roots

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

Recurrence

\(P_{n}(x) = \left(-4 - 9\,x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)

Rows ?

nx0x1x2x3x4x5x6x7Pn(1)
011
1-4-9-13
2167281169
3-64-432-972-729-2197
42562304777611664656128561
5-1024-11520-51840-116640-131220-59049-371293
6409655296311040933120157464014171765314414826809
7-16384-258048-1741824-6531840-14696640-19840464-14880348-4782969-62748517
Technical details
Node id
n-3ac4aedfd42ceede · revision 0 · JSON
Definition source
derived:basis_map_A013610
Fingerprint
f6-12e1fe8c90bb4450

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:      -4,       -9;
  2:      16,       72,        81;
  3:     -64,     -432,      -972,       -729;
  4:     256,     2304,      7776,      11664,       6561;
  5:   -1024,   -11520,    -51840,    -116640,    -131220,      -59049;
  6:    4096,    55296,    311040,     933120,    1574640,     1417176,      531441;
  7:  -16384,  -258048,  -1741824,   -6531840,  -14696640,   -19840464,   -14880348,    -4782969;
  8:   65536,  1179648,   9289728,   41803776,  117573120,   211631616,   238085568,   153055008,    43046721;
  9: -262144, -5308416, -47775744, -250822656, -846526464, -1904684544, -2857026816, -2754990144, -1549681956, -387420489;
%F Formula
The row polynomials satisfy P(n,x) = -(4+9*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[-(4 + 9*x)*P[n - 1, 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] = -(4 + 9*x)*v[i - 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.