A085881 → basis A013609 → basis A013610

nonnegative coefficientsonly rational roots

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

Recurrence

\(P_{n}(x) = \left(-4 - 6\,x + 8\,n + 12\,n x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)

Rows ?

nx0x1x2x3x4x5x6x7Pn(1)
011
14610
248144108300
396043206480324015000
4268801612803628803628801360801050000
59676807257600217728003265920024494400734832094500000
642577920383201280143700480028740096003233260800193995648048498912010395000000
7221405184023247544320104613949440261534873600392302310400353072079360176536039680378291513601351350000000
Technical details
Node id
n-1e792e6766e7cb36 · revision 0 · JSON
Definition source
derived:basis_map_A013610
Fingerprint
f6-f06e51c139cfae05

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:             4,               6;
  2:            48,             144,             108;
  3:           960,            4320,            6480,             3240;
  4:         26880,          161280,          362880,           362880,           136080;
  5:        967680,         7257600,        21772800,         32659200,         24494400,          7348320;
  6:      42577920,       383201280,      1437004800,       2874009600,       3233260800,       1939956480,        484989120;
  7:    2214051840,     23247544320,    104613949440,     261534873600,     392302310400,     353072079360,     176536039680,      37829151360;
  8:  132843110400,   1594117324800,   8369115955200,   25107347865600,   47076277248000,   56491532697600,   42368649523200,   18157992652800,    3404623622400;
  9: 9033331507200, 121949975347200, 731699852083200, 2560949482291200, 5762136335155200, 8643204502732800, 8643204502732800, 5556345751756800, 2083629656908800, 347271609484800;
%F Formula
The row polynomials satisfy P(n,x) = (8*n-4+(12*n-6)*x)*P(n-1,x) for n >= 1, with P(0,x) = 1.
%t Mathematica
P[0, x_] := 1;
P[n_, x_] := P[n, x] = Expand[(8*n - 4 + (12*n - 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; for(n = 1, N, my(i = n + 1); v[i] = (8*n - 4 + (12*n - 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

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.