A038326 → basis A013609

nonnegative coefficients only rational roots

Proved for all n: all roots real, in (−∞, 0] · coefficients of one sign · Hadamard kernel what this means

Recurrence
\(P_{n}(x) = \left(23 + 24\,x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)

Rows ?

nx0x1x2x3x4x5x6x7Pn(1)
011
1232447
252911045762209
312167380883974413824103823
42798411168032182822412718083317764879681
56436343335809207008192073128960381542407962624229345007
6148035889926833392241782624033639321602632642560109884211219110297610779215329
73404825447248700293527785400492813539826944014128515072088456790016307675791364586471424506623120463

Generated b-files: A009991 (row sums) ?

Computed in your browser ?

Technical details
Node id
n-3afaca41e5482e8c · revision 1 · JSON
Definition source
derived:basis_map_A013609
Fingerprint
f6-723ac5bf98d71a32

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

OEIS matches ?

A generated b-file is computed from the node's definition along the row alignment of its OEIS link and starts at the entry's offset. It is an identification on a finite prefix, not a proof that the node and the OEIS entry agree for every n.

OEIS submission text ?

Fields to paste into an OEIS submission: the example %e, the formula %F and programs %t (Mathematica) and %o (PARI/GP) that list the same rows. For an OEIS link the row numbers, the offset and the orientation are those of the entry, as matched; the matched terms were compared with the published ones, which identifies the node with the entry on a finite prefix, not for every n. The PARI/GP program is not machine-checked here.

The atlas's own rows: n = 0, …, ascending powers of x
%e Example
Triangle begins:
  0:             1;
  1:            23,             24;
  2:           529,           1104,            576;
  3:         12167,          38088,          39744,           13824;
  4:        279841,        1168032,        1828224,         1271808,          331776;
  5:       6436343,       33580920,       70081920,        73128960,        38154240,         7962624;
  6:     148035889,      926833392,     2417826240,      3363932160,      2632642560,      1098842112,       191102976;
  7:    3404825447,    24870029352,    77854004928,    135398269440,    141285150720,     88456790016,     30767579136,     4586471424;
  8:   78310985281,   653726485824,  2387522817792,   4982656315392,   6499116933120,   5425349787648,   2830617280512,   843910742016,   110075314176;
  9: 1801152661463, 16915172820696, 70602460468992, 171901642881024, 269063441031168, 280761851510784, 195312592355328, 87344761798656, 22785590034432, 2641807540224;
%F Formula
The row polynomials satisfy P(n,x) = (23+24*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[(23 + 24*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] = (23 + 24*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)

Generated with polytool c48629374597.

Proved properties

  • Real-rooted. Every row P_n, n >= 0, is zero or real-rooted with all roots in (-inf, 0]
    Every polynomial of the sequence has only real roots, inside the stated interval.
    by the cited steps: e-15af34f262d68ea6
  • Coefficients of one sign. Every nonzero row, n >= 0: the coefficients of P_n have one sign
    All coefficients of each polynomial have the same sign (after x -> -x when alternating).
    derived from the cited steps by a stated theorem: e-15af34f262d68ea6
  • Hadamard kernel (Malo). Rows P_n, n >= 0, are Hadamard kernels (preserve real-rootedness)
    Multiplying the coefficients of any real-rooted polynomial termwise by those of a row (Hadamard product) gives a real-rooted polynomial again.
    derived from the cited steps by a stated theorem: e-15af34f262d68ea6

Proof chains

1 incoming proof step. Each step is expanded back to the roots of the proof DAG, the theorem checks of a node's own rule. JSON

No candidate equalities or related sequences.

References

  1. [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