A038330 → D

nonnegative coefficientsonly rational roots

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

Recurrence

\(\left(1 + n\right)\,P_{n}(x) = \left(24 + 8\,x + 12\,n + 4\,n x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 96 + 32\,x\)

Rows ?

nx0x1x2x3x4x5x6x7x8Pn(1)
09632128
1172811521923072
227648276489216102465536
34147205529602764806144051201310720
459719689953280663552022118403686402457625165824
58360755216721510413934592061931520154828802064384114688469762048
6114661785626754416642675441664148635648049545216099090432110100485242888589934592
715479341056412782428164815794995232105299968133772083203567255552594542592566231042359296154618822656
Technical details
Node id
n-828a2cbad9f7fbdf · revision 0 · JSON
Definition source
derived:derivative
Fingerprint
f6-f9762973ec1089d7

Observed on the stored rows ?

  • Degrees: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 (affine: slope 1, intercept 1)
  • 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:            96,            32;
  1:          1728,          1152,            192;
  2:         27648,         27648,           9216,           1024;
  3:        414720,        552960,         276480,          61440,          5120;
  4:       5971968,       9953280,        6635520,        2211840,        368640,         24576;
  5:      83607552,     167215104,      139345920,       61931520,      15482880,       2064384,       114688;
  6:    1146617856,    2675441664,     2675441664,     1486356480,     495452160,      99090432,     11010048,       524288;
  7:   15479341056,   41278242816,    48157949952,    32105299968,   13377208320,    3567255552,    594542592,     56623104,     2359296;
  8:  206391214080,  619173642240,   825564856320,   642105999360,  321052999680,  107017666560,  23781703680,   3397386240,   283115520,   10485760;
  9: 2724364025856, 9081213419520, 13621820129280, 12108284559360, 7063165992960, 2825266397184, 784796221440, 149484994560, 18685624320, 1384120320, 46137344;
%F Formula
The row polynomials satisfy (n+1)*P(n,x) = (12*n+24+(4*n+8)*x)*P(n-1,x) for n >= 1, with P(0,x) = 96 + 32*x.
%t Mathematica
P[0, x_] := 96 + 32*x;
P[n_, x_] := P[n, x] = Expand[Together[((12*n + 24 + (4*n + 8)*x)*P[n - 1, x])/(n + 1)]];
Table[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten
%o PARI/GP
P(N) = {my(v = vector(N + 1)); v[1] = 96 + 32*x; for(n = 1, N, my(i = n + 1); v[i] = ((12*n + 24 + (4*n + 8)*x)*v[i - 1])/(n + 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. [Bra06] Petter Brändén. On linear transformations preserving the Pólya frequency property. Transactions of the American Mathematical Society, 358(8):3697–3716, February 2006. doi:10.1090/s0002-9947-06-03856-6
  2. [Bra15] Petter Brändén. Unimodality, log-concavity, real-rootedness and beyond. Handbook of enumerative combinatorics, :437–483, March 2015. doi:10.1201/b18255-10
  3. [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
  4. [SP14] J Schur and G Polya. Über zwei Arten von Faktorenfolgen in der Theorie der algebraischen Gleichungen. J. Reine Angew. Math., 1914.