A038330 → basis A013609 → D

nonnegative coefficientsonly rational roots

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

Recurrence

\(\left(1 + n\right)\,P_{n}(x) = \left(32 + 16\,x + 16\,n + 8\,n x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 256 + 128\,x\)

Rows ?

nx0x1x2x3x4x5x6x7x8Pn(1)
0256128384
161446144153613824
21310721966089830416384442368
3262144052428803932160131072016384013271040
45033164812582912012582912062914560157286401572864382205952
59395240962818572288352321536023488102408808038401761607681468006410701766656
61717986918460129542144901943132167516192768037580963840112742891521879048192134217728293534171136
730923764531212369505812482164663517184216466351718413529146982405411658792961352914698241932735283212079595527925422620672
Technical details
Node id
n-69e147a1d9b34e2b · revision 0 · JSON
Definition source
derived:derivative
Fingerprint
f6-11aec07ce60b6d61

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:            256,             128;
  1:           6144,            6144,             1536;
  2:         131072,          196608,            98304,            16384;
  3:        2621440,         5242880,          3932160,          1310720,           163840;
  4:       50331648,       125829120,        125829120,         62914560,         15728640,         1572864;
  5:      939524096,      2818572288,       3523215360,       2348810240,        880803840,       176160768,        14680064;
  6:    17179869184,     60129542144,      90194313216,      75161927680,      37580963840,     11274289152,      1879048192,      134217728;
  7:   309237645312,   1236950581248,    2164663517184,    2164663517184,    1352914698240,    541165879296,    135291469824,    19327352832,     1207959552;
  8:  5497558138880,  24739011624960,   49478023249920,   57724360458240,   43293270343680,  21646635171840,   7215545057280,  1546188226560,   193273528320,   10737418240;
  9: 96757023244288, 483785116221440, 1088516511498240, 1451355348664320, 1269935930081280, 761961558048768, 317483982520320, 90709709291520, 17008070492160, 1889785610240, 94489280512;
%F Formula
The row polynomials satisfy (n+1)*P(n,x) = (16*n+32+(8*n+16)*x)*P(n-1,x) for n >= 1, with P(0,x) = 256 + 128*x.
%t Mathematica
P[0, x_] := 256 + 128*x;
P[n_, x_] := P[n, x] = Expand[Together[((16*n + 32 + (8*n + 16)*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] = 256 + 128*x; for(n = 1, N, my(i = n + 1); v[i] = ((16*n + 32 + (8*n + 16)*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.