A134346 → x ↦ x+1

nonnegative coefficientsonly rational roots

Proved for all n all roots real, in (−∞, −1]coefficients of one signHadamard kernelinterlacing (weak)

Recurrence

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

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
011
1639
22828763
31201809015405
4496992744248312511
520165040504025206306315309
681282438430480203207620152412792583
73264011424017136014280071400214203570255557685
81308165232649157129157125723202289285723281765113352671
95237762356992471398454996484124736206236868745614731218414102320135709
102096128104806402358144031441920275116801650700868779201965120368460409402047120873303
1183865604612608011531520017297280017297280012108096060540480216216005405400900900900904095725416965
123355033620130201655358054492263424010379635208303708164843829762075927046487272014416160216242419658481914353033231
131342095368723619842617085952479799091259974886405397739776359849318417992465926747174721874215203748430451114964259581638326119793709
14536854528375798169612213440512244268810243358696140833586961408251902210561439441203262975552642099185088524796272954175041192718891747632767156723545223
Technical details
Node id
n-65a2790ea28179de · revision 0 · JSON
Definition source
derived:shift_x_plus_one
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:      6,       3;
  2:     28,      28,       7;
  3:    120,     180,      90,      15;
  4:    496,     992,     744,     248,      31;
  5:   2016,    5040,    5040,    2520,     630,      63;
  6:   8128,   24384,   30480,   20320,    7620,    1524,    127;
  7:  32640,  114240,  171360,  142800,   71400,   21420,   3570,    255;
  8: 130816,  523264,  915712,  915712,  572320,  228928,  57232,   8176,   511;
  9: 523776, 2356992, 4713984, 5499648, 4124736, 2062368, 687456, 147312, 18414, 1023;
%F Formula
The row polynomials satisfy P(n,x) = -(8+8*x+2*x^2)*P(n-2,x) + (6+3*x)*P(n-1,x) for n >= 2, with P(0,x) = 1, P(1,x) = 6 + 3*x.
%t Mathematica
P[0, x_] := 1;
P[1, x_] := 6 + 3*x;
P[n_, x_] := P[n, x] = Expand[-(8 + 8*x + 2*x^2)*P[n - 2, x] + (6 + 3*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] = 6 + 3*x; for(n = 2, N, my(i = n + 1); v[i] = -(8 + 8*x + 2*x^2)*v[i - 2] + (6 + 3*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

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