A131436 → basis A013609

nonnegative coefficientsonly rational roots

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

Recurrence

\(P_{n}(x) = \left(-2 - 8\,x - 8\,x^{2}\right)\,P_{n-2}(x) + \left(3 + 6\,x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)
\(P_{1}(x) = 3 + 6\,x\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
011
1369
27282863
31590180120405
4312487449924962511
563630252050405040201615309
612715247620203203048024384812892583
72553570214207140014280017136011424032640557685
85118176572322289285723209157129157125232641308163352671
91023184141473126874562062368412473654996484713984235699252377620135709
102047409403684601965120687792016507008275116803144192023581440104806402096128120873303
1140959009090090054054002162160060540480121080960172972800172972800115315200461260808386560725416965
128191196584216242414416160648727202075927044843829768303708161037963520922634240553580544201302016335503364353033231
131638342595851114963748430418742152067471747217992465923598493184539773977659974886404797990912261708595287236198413420953626119793709
14327679174761192718895417504524796272209918508862975552641439441203225190221056335869614083358696140824426881024122134405123757981696536854528156723545223
Technical details
Node id
n-0ee74d387e65778a · revision 0 · JSON
Definition source
derived:basis_map_A013609
Fingerprint
f6-11aec07ce60b6d61

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

Matches ?

No OEIS matches.

Submission text ?

Atlas rows n = 0, …, ascending powers of x
%e Example
Triangle begins:
  0:    1;
  1:    3,     6;
  2:    7,    28,     28;
  3:   15,    90,    180,    120;
  4:   31,   248,    744,    992,     496;
  5:   63,   630,   2520,   5040,    5040,    2016;
  6:  127,  1524,   7620,  20320,   30480,   24384,    8128;
  7:  255,  3570,  21420,  71400,  142800,  171360,  114240,   32640;
  8:  511,  8176,  57232, 228928,  572320,  915712,  915712,  523264,  130816;
  9: 1023, 18414, 147312, 687456, 2062368, 4124736, 5499648, 4713984, 2356992, 523776;
%F Formula
The row polynomials satisfy P(n,x) = -(2+8*x+8*x^2)*P(n-2,x) + (3+6*x)*P(n-1,x) for n >= 2, with P(0,x) = 1, P(1,x) = 3 + 6*x.
%t Mathematica
P[0, x_] := 1;
P[1, x_] := 3 + 6*x;
P[n_, x_] := P[n, x] = Expand[-(2 + 8*x + 8*x^2)*P[n - 2, x] + (3 + 6*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; v[2] = 3 + 6*x; for(n = 2, N, my(i = n + 1); v[i] = -(2 + 8*x + 8*x^2)*v[i - 2] + (3 + 6*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

Candidate equalities ?

Same fingerprint ?

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