A178820 → basis A013609 → basis A013609

palindromicγ-positivenonnegative coefficientsonly rational roots

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

Recurrence

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

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
011
1161632
2160320160640
3128038403840128010240
489603584053760358408960143360
557344286720573440573440286720573441835008
63440642064384516096068812805160960206438434406422020096
719660801376256041287680688128006881280041287680137625601966080251658240
8108134408650752030277632060555264075694080060555264030277632086507520108134402768240640
9576716805190451202076180480484442112072666316807266631680484442112020761804805190451205767168029527900160
102998927362998927360134951731203598712832062977474560755729694726297747456035987128320134951731202998927360299892736307090161664
1115267266561679399321683969966080251909898240503819796480705347715072705347715072503819796480251909898240839699660801679399321615267266563126736191488
12763363328091603599360503819796480167939932160037786484736006045837557760705347715072060458375577603778648473600167939932160050381979648091603599360763363328031267361914880
133758096384048855252992029313151795201074815565824026870389145600483667004620806448893394944064488933949440483667004620802687038914560010748155658240293131517952048855252992037580963840307863255777280
1418253611008025555055411201661078601728066443144069120182718646190080365437292380160548155938570240626463929794560548155938570240365437292380160182718646190080664431440691201661078601728025555055411201825361100802990671627550720
Technical details
Node id
n-53b416f9268fb8ce · revision 0 · JSON
Definition source
derived:basis_map_A013609
Fingerprint
f6-77a7ed3b1d5f257e

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: yes
  • γ-positive (gamma_positive): yes
  • 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:       16,        16;
  2:      160,       320,        160;
  3:     1280,      3840,       3840,       1280;
  4:     8960,     35840,      53760,      35840,       8960;
  5:    57344,    286720,     573440,     573440,     286720,      57344;
  6:   344064,   2064384,    5160960,    6881280,    5160960,    2064384,     344064;
  7:  1966080,  13762560,   41287680,   68812800,   68812800,   41287680,   13762560,    1966080;
  8: 10813440,  86507520,  302776320,  605552640,  756940800,  605552640,  302776320,   86507520,  10813440;
  9: 57671680, 519045120, 2076180480, 4844421120, 7266631680, 7266631680, 4844421120, 2076180480, 519045120, 57671680;
%F Formula
The row polynomials satisfy n*P(n,x) = (4*n+12+(4*n+12)*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[Together[((4*n + 12 + (4*n + 12)*x)*P[n - 1, x])/(n)]];
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] = ((4*n + 12 + (4*n + 12)*x)*v[i - 1])/(n)); 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.