A038314 → basis A013609

nonnegative coefficients only rational roots

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

Recurrence
\(P_{n}(x) = \left(22 + 24\,x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 484 + 1056\,x + 576\,x^{2}\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9Pn(1)
048410565762116
11064834848380161382497336
22342561022208167270412165123317764477456
35153632281107206133248066908160364953607962624205962976
411337990474212300820239718402943959040240869376010510663681911029769474296896
52494357888190478238726233833267211334242304012364627968080932110336294298583044586471424435817657216
6548758735364789167144961828591091712398965329100854404363059204748017139712258982753075280721897062411007531417620047612231936
71207269217792118531886837765172300516556813165855860326421544127771443223502684841574417092861702963279914678091776217949122068482641807540224922190162669056

Computed in your browser ?

Technical details
Node id
n-2a3c7d06bf210d3a · revision 1 · JSON
Definition source
derived:basis_map_A013609
Fingerprint
f6-60cc3cc9b4461a16

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:             484,             1056,               576;
  1:           10648,            34848,             38016,              13824;
  2:          234256,          1022208,           1672704,            1216512,             331776;
  3:         5153632,         28110720,          61332480,           66908160,           36495360,            7962624;
  4:       113379904,        742123008,        2023971840,         2943959040,         2408693760,         1051066368,          191102976;
  5:      2494357888,      19047823872,       62338332672,       113342423040,       123646279680,        80932110336,        29429858304,         4586471424;
  6:     54875873536,     478916714496,     1828591091712,      3989653291008,      5440436305920,      4748017139712,      2589827530752,       807218970624,       110075314176;
  7:   1207269217792,   11853188683776,    51723005165568,    131658558603264,    215441277714432,    235026848415744,    170928617029632,     79914678091776,     21794912206848,     2641807540224;
  8:  26559922791424,  289744612270080,  1422382642053120,   4137840413245440,   7899513516195840,  10341181330292736,   9401073936629760,   5860409726730240,   2397440342753280,   581197658849280,    63403380965376;
  9: 584318301411328, 7011819616935936, 38246288819650560, 125169672500674560, 273097467274199040, 417094313655140352, 455011978532880384, 354554788467179520, 193393520982097920, 70324916720762880, 15343618193620992, 1521681143169024;
%F Formula
The row polynomials satisfy P(n,x) = (22+24*x)*P(n-1,x) for n >= 1, with P(0,x) = 484 + 1056*x + 576*x^2.
%t Mathematica
P[0, x_] := 484 + 1056*x + 576*x^2;
P[n_, x_] := P[n, x] = Expand[(22 + 24*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] = 484 + 1056*x + 576*x^2; for(n = 1, N, my(i = n + 1); v[i] = (22 + 24*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-61350e73fec19600
  • 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-61350e73fec19600
  • 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-61350e73fec19600

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 (3)

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