A099093 → x ↦ x−10

Proved for all n: all roots real, in (26/3, 10] · alternating coefficient signs · interlacing (weak) what this means

Recurrence
\(P_{n}(x) = \left(-30 + 3\,x\right)\,P_{n-1}(x) + \left(-30 + 3\,x\right)\,P_{n-2}(x)\)
\(P_{0}(x) = 1\)
\(P_{1}(x) = -30 + 3\,x\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
011
1-303-27
2870-1779702
3-252007740-79227-18225
4729900-29988046179-315981473121
5-2114100010878300-2238030230121-11826243-12282192
6612333000-37858590097490790-133844131033236-42525729318844917
7-1773576000012804804000-3960705600680387040-701051764332690-1487162187-8277193575
8513702810000-424156824000153175098600-315997232404073166081-33592077017310105-5095716561214875413766
9-1487901150000013828461750000-57104878500001375223265000-21284983575021956825115-150960591066705687-171898219683-5578151945157
10430959260700000-445225073850000206932297320000-5698064450700010294170715350-1274957139357109631587185-6462770895249960978-572775359049144808466347557
11-1248240747600000014190139110600000-73308441204000002271828065670000-46925589011400067833972066060-7002660380976516247900065-26635455504915968088-18895680177147-3759218488864800
12361543446459000000-448501765748400000254952096802650000-8781715810413000020413393845448500-3373655605997040406467908593839-359726402564732320920223290-1064636936283295819935-6182430353144197589070607965561
13-1047183116949000000014076531916083000000-87315724603809000003309223659200550000-854960128775415000159007062883932900-219014223481788302262087515330829-17519772010280410049286069558-41495090427011680187445-2008846981594323-2533406007215720547
14303308631690930000000-439171767679131000000295182701358351300000-12207205612362735000034700621551188255000-71726424231279753001111748855021357310-13126830957098565311864648621608488-81691507091644242178119657840-158351614726540865687136-648889461478296965767057288409384622

Computed in your browser ?

Technical details
Node id
n-e2dcd39fb6d71722 · revision 1 · JSON
Definition source
derived:basis_map_coefficients_of:oeis_catalog:A099093
Fingerprint
f6-c7b2b5fef74944cb

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): 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:               1;
  1:             -30,              3;
  2:             870,           -177,              9;
  3:          -25200,           7740,           -792,            27;
  4:          729900,        -299880,          46179,         -3159,            81;
  5:       -21141000,       10878300,       -2238030,        230121,        -11826,         243;
  6:       612333000,     -378585900,       97490790,     -13384413,       1033236,      -42525,         729;
  7:    -17735760000,    12804804000,    -3960705600,     680387040,     -70105176,     4332690,     -148716,     2187;
  8:    513702810000,  -424156824000,   153175098600,  -31599723240,    4073166081,  -335920770,    17310105,  -509571,     6561;
  9: -14879011500000, 13828461750000, -5710487850000, 1375223265000, -212849835750, 21956825115, -1509605910, 66705687, -1718982, 19683;
%F Formula
The row polynomials satisfy P(n,x) = -(30-3*x)*P(n-1,x) - (30-3*x)*P(n-2,x) for n >= 2, with P(0,x) = 1, P(1,x) = -30 + 3*x.
%t Mathematica
P[0, x_] := 1;
P[1, x_] := -30 + 3*x;
P[n_, x_] := P[n, x] = Expand[-(30 - 3*x)*P[n - 1, x] - (30 - 3*x)*P[n - 2, x]];
Table[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten
%o PARI/GP
P(N) = {my(v = vector(N + 1)); v[1] = 1; v[2] = -30 + 3*x; for(n = 2, N, my(i = n + 1); v[i] = -(30 - 3*x)*v[i - 1] - (30 - 3*x)*v[i - 2]); 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 (26/3, 10]
    Every polynomial of the sequence has only real roots, inside the stated interval.
    by the cited steps: e-d18687645e4e9661
  • Coefficients of one sign. Every nonzero row, n >= 0: the coefficients of P_n(-x) 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-d18687645e4e9661
  • Interlacing of consecutive rows. Rows P_(m-1), P_m interlace (weak, unordered) for every m >= 1
    The roots of consecutive polynomials alternate on the real line.
    by the cited steps: e-d18687645e4e9661

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

Used in 1 proof step

No candidate equalities or related sequences.

References

  1. [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