A038338 → basis A008277

nonnegative coefficients

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

Recurrence
\(P_{n}(x) = \left(24 + 12\,x\right)\,P_{n-1}(x) + \left(12\,x\right)\,P_{n-1}'(x)\)
\(P_{0}(x) = 576 + 720\,x + 144\,x^{2}\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9Pn(1)
05767201441440
1138243283215552172863936
233177613478401140480290304207363131136
379626245250355270917120311040004976640248832167712768
41911029761985679360403406438427172454407315660808062156829859849743265792
54586471424737776926722174632427522114434990088527970304015551004672125411328035831808609391558656
611007531417627110345932801132356796416015296168853504867746060697623296408289283070069309441891919462442998169640774304268288
7264180754022498918149128192576063677399040105365294678016080833118994432029981935691366457428355317760572735619072027862813900851597803522902866627133440

Computed in your browser ?

Technical details
Node id
n-085c06a40df81890 · revision 1 · JSON
Definition source
derived:basis_map_A008277
Fingerprint
f6-b5f1389370a379f1

Observed on the stored rows ?

  • Degrees: 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 (affine: slope 1, intercept 2)
  • 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): no

OEIS matches ?

No OEIS matches.

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:              576,                720,                 144;
  1:            13824,              32832,               15552,                1728;
  2:           331776,            1347840,             1140480,              290304,               20736;
  3:          7962624,           52503552,            70917120,            31104000,             4976640,              248832;
  4:        191102976,         1985679360,          4034064384,          2717245440,           731566080,            80621568,             2985984;
  5:       4586471424,        73777692672,        217463242752,        211443499008,         85279703040,         15551004672,          1254113280,           35831808;
  6:     110075314176,      2711034593280,      11323567964160,      15296168853504,       8677460606976,       2329640828928,        307006930944,        18919194624,         429981696;
  7:    2641807540224,     98918149128192,     576063677399040,    1053652946780160,     808331189944320,     299819356913664,      57428355317760,      5727356190720,      278628139008,       5159780352;
  8:   63403380965376,   3592755059097600,   28838074304692224,   70131940935598080,   70843681037352960,   34884800260079616,    9110954393468928,   1307694732410880,   102163650969600,    4024628674560,    61917364224;
  9: 1521681143169024, 130100022699098112, 1427340627334397952, 4553973347792191488, 5942328325916590080, 3780447394294923264, 1293269224893972480, 250562483822002176, 27951974905282560, 1757214796677120, 57211644542976, 743008370688;
%F Formula
The row polynomials satisfy P(n,x) = (24+12*x)*P(n-1,x) + 12*x*d/dx P(n-1,x) for n >= 1, with P(0,x) = 576 + 720*x + 144*x^2.
%t Mathematica
P[0, x_] := 576 + 720*x + 144*x^2;
P[n_, x_] := P[n, x] = Expand[(24 + 12*x)*P[n - 1, x] + 12*x*D[P[n - 1, x], x]];
Table[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten
%o PARI/GP
P(N) = {my(v = vector(N + 1)); v[1] = 576 + 720*x + 144*x^2; for(n = 1, N, my(i = n + 1); v[i] = (24 + 12*x)*v[i - 1] + 12*x*deriv(v[i - 1], 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)

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-44f842c6e5783c9b
  • 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-44f842c6e5783c9b
  • 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-44f842c6e5783c9b

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

Same fingerprint (19)

Equal up to content, sign, reversal and a small index shift.

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
  2. [MW08] Shi-Mei Ma and Yi Wang. q-Eulerian polynomials and polynomials with only real zeros. The Electronic Journal of Combinatorics, 15(1):Research Paper 17, January 2008. doi:10.37236/741