A120910 → basis A007318 → basis A013609

nonnegative coefficientsonly rational roots

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

Recurrence

\(P_{n}(x) = \left(4 + 2\,x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 3\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
033
112618
2484812108
319228814424648
476815361152384483888
530727680768038409609623328
612288368644608030720115202304192139968
749152172032258048215040107520322565376384839808
81966087864321376256137625686016034406486016122887685038848
978643235389447077888825753661931523096576103219222118427648153630233088
1031457281572864035389440471859204128768024772608103219202949120552960614403072181398528
11125829126920601617301504025952256025952256018166579290832896324403208110080135168013516861441088391168
125033164830198988883047219213841203201557135360124570828872666316831142707297320960216268803244032294912122886530347008
13201326592130862284839258685447197425664899678208080971038725398069248269903462410121379842811494405622988876677126389762457639182082048
1480530636856371445761832071987236641439744503819796485038197964837786484736215922769929446621184314887372878721843214313062417891328137625649152235092492288
Technical details
Node id
n-ffa298ba6eae841f · revision 0 · JSON
Definition source
derived:basis_map_A013609
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:      3;
  1:     12,       6;
  2:     48,      48,      12;
  3:    192,     288,     144,      24;
  4:    768,    1536,    1152,     384,      48;
  5:   3072,    7680,    7680,    3840,     960,      96;
  6:  12288,   36864,   46080,   30720,   11520,    2304,     192;
  7:  49152,  172032,  258048,  215040,  107520,   32256,    5376,    384;
  8: 196608,  786432, 1376256, 1376256,  860160,  344064,   86016,  12288,   768;
  9: 786432, 3538944, 7077888, 8257536, 6193152, 3096576, 1032192, 221184, 27648, 1536;
%F Formula
The row polynomials satisfy P(n,x) = (4+2*x)*P(n-1,x) for n >= 1, with P(0,x) = 3.
%t Mathematica
P[0, x_] := 3;
P[n_, x_] := P[n, x] = Expand[(4 + 2*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] = 3; for(n = 1, N, my(i = n + 1); v[i] = (4 + 2*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.