A028326 → basis A013611 → basis A013609

nonnegative coefficientsonly rational roots

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

Recurrence

\(P_{n}(x) = \left(6 + 8\,x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 2\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
022
1121628
272192128392
34321728230410245488
42592138242764824576819276832
515552103680276480368640245760655361075648
693312746496248832044236804423680235929652428815059072
7559872522547220901888464486406193152049545216220200964194304210827008
8335923235831808167215104445906944743178240792723456528482304201326592335544322951578112
9201553922418647041289945088401316249680263249921070176665695126814725435817984181193932826843545641322093568
1012093235216124313609674588160343985356808026324992012842119987214269022208010871635968054358179840161061273602147483648578509309952
1172559411210642046976709469798402837879193607567677849601412633198592188351093145617938199347201195879956480531502202880141733920768171798691848099130339328
1243535646726965703475251081825484822703033548806810910064640145299414712322260213117747225831007059968215258392166401275605286912051024211476481236950581248137438953472113387824750592
132612138803245277072588836221658071041770836616806459027887226880141666929344512251852318834688335803091779584335803091779584248743030947840132662949838848482410726686721072023837081610995116277761587429546508288
14156728328192292559545958425355160649728135227523465216495834252705792132222467388211226444493477642244029637101355008470124328491417641788829199237122785921946615808135075003472281645025001157427292358976733184879609302220822224013651116032
Technical details
Node id
n-b6d6a2cd98c37986 · revision 0 · JSON
Definition source
derived:basis_map_A013609
Fingerprint
f6-c91d5d506c107735

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:        2;
  1:       12,        16;
  2:       72,       192,        128;
  3:      432,      1728,       2304,       1024;
  4:     2592,     13824,      27648,      24576,       8192;
  5:    15552,    103680,     276480,     368640,     245760,       65536;
  6:    93312,    746496,    2488320,    4423680,    4423680,     2359296,     524288;
  7:   559872,   5225472,   20901888,   46448640,   61931520,    49545216,   22020096,    4194304;
  8:  3359232,  35831808,  167215104,  445906944,  743178240,   792723456,  528482304,  201326592,   33554432;
  9: 20155392, 241864704, 1289945088, 4013162496, 8026324992, 10701766656, 9512681472, 5435817984, 1811939328, 268435456;
%F Formula
The row polynomials satisfy P(n,x) = (6+8*x)*P(n-1,x) for n >= 1, with P(0,x) = 2.
%t Mathematica
P[0, x_] := 2;
P[n_, x_] := P[n, x] = Expand[(6 + 8*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] = 2; for(n = 1, N, my(i = n + 1); v[i] = (6 + 8*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.