A178821 → basis A013610 → reverse

nonnegative coefficientsonly rational roots

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

Recurrence

\(\left(n\right)\,P_{n}(x) = \left(12 + 8\,x + 3\,n + 2\,n x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
011
1151025
213518060375
3945189012602804375
4567015120151206720112043750
53061810206013608090720302404032393750
61530906123601020600907200453600120960134403281250
7721710336798067359607484400498960019958404435204224025781250
83247695173210404041576053887680449064002395008079833601520640126720193359375
914073345844400702251735203502699203502699202335132801037836802965248049420803660801396484375
1059108049394053660118216098021016195202451889440196151155210897286404151347201037836801537536010250249775390625
112418056551773241470591080490011821609800157621464001471133664098075577604670265600155675520034594560046126080279552066650390625
129672226207737780960283718635206304858560094572878400100877736960784604620804483454976018681062400553512960011070259201341849607454720444335937500
1337944887403288556908013154227632032154778656053591297760064309557312057164050944038109367296019054683648070572902400188194406403421716480380190720194969602905273437500
1414635885140136601594640591940243440157850731584028939300790403858573438720385857343872029398654771201714921528320762187345920254062448640615908966401026514944010528358405013504018676757812500
Technical details
Node id
n-eb695a28a5855a3c · revision 0 · JSON
Definition source
derived:reversal
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:       15,       10;
  2:      135,      180,        60;
  3:      945,     1890,      1260,       280;
  4:     5670,    15120,     15120,      6720,      1120;
  5:    30618,   102060,    136080,     90720,     30240,      4032;
  6:   153090,   612360,   1020600,    907200,    453600,    120960,     13440;
  7:   721710,  3367980,   6735960,   7484400,   4989600,   1995840,    443520,    42240;
  8:  3247695, 17321040,  40415760,  53887680,  44906400,  23950080,   7983360,  1520640,  126720;
  9: 14073345, 84440070, 225173520, 350269920, 350269920, 233513280, 103783680, 29652480, 4942080, 366080;
%F Formula
The row polynomials satisfy n*P(n,x) = (3*n+12+(2*n+8)*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[((3*n + 12 + (2*n + 8)*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] = ((3*n + 12 + (2*n + 8)*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.