A038337 → basis A007318

nonnegative coefficients only rational roots

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

Recurrence
\(P_{n}(x) = \left(23 + 11\,x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 529 + 506\,x + 121\,x^{2}\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9Pn(1)
05295061211156
112167174578349133139304
2279841535348384054122452146411336336
3643634315391255147220707040990168371516105145435424
41480358894247986385079114153238855401161763352222503817715611544804416
53404825447113987634531635474756313036392985623479664517891155592852213211948717152523350144
6783109852812996246393365015455919324797392618482868006456701097324209522624036153235856394642143588811785793904896
7180115266146377527875428191483141964713216551004533756118735467307385678652784266181058494570837111368452444372288367235794769160716992766464

Computed in your browser ?

Technical details
Node id
n-19327cf22807de6e · revision 1 · JSON
Definition source
derived:basis_map_A007318
Fingerprint
f6-2f74b0bddfe64ff1

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): yes

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:             529,              506,               121;
  1:           12167,            17457,              8349,              1331;
  2:          279841,           535348,            384054,            122452,             14641;
  3:         6436343,         15391255,          14722070,           7040990,           1683715,            161051;
  4:       148035889,        424798638,         507911415,         323885540,         116176335,          22225038,          1771561;
  5:      3404825447,      11398763453,       16354747563,       13036392985,        6234796645,        1789115559,        285221321,         19487171;
  6:     78310985281,     299624639336,      501545591932,      479739261848,      286800645670,      109732420952,      26240361532,       3585639464,       214358881;
  7:   1801152661463,    7752787542819,    14831419647132,    16551004533756,    11873546730738,     5678652784266,    1810584945708,     371113684524,     44372288367,     2357947691;
  8:  41426511213649,  198126792760930,   426403314855045,   543818720394840,   455152624678290,   261218028076236,  104108634378210,   28452049146840,   5102813162205,   542327968930,   25937424601;
  9: 952809757913927, 5012607856851529, 11986670962036265, 17198267032486815, 16450516291943910, 11014693517214618, 5267896899537426, 1799592108537630, 430337243345955, 68604488069645, 6562168424053, 285311670611;
%F Formula
The row polynomials satisfy P(n,x) = (23+11*x)*P(n-1,x) for n >= 1, with P(0,x) = 529 + 506*x + 121*x^2.
%t Mathematica
P[0, x_] := 529 + 506*x + 121*x^2;
P[n_, x_] := P[n, x] = Expand[(23 + 11*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] = 529 + 506*x + 121*x^2; for(n = 1, N, my(i = n + 1); v[i] = (23 + 11*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-347b6efdbfa5233f
  • 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-347b6efdbfa5233f
  • 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-347b6efdbfa5233f

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