A132200 → basis A013610

nonnegative coefficientsonly rational roots

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

Recurrence

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

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
011
181220
2164836100
332144216108500
4643848648643242500
512896028804320324097212500
625623048640172801944011664291662500
7512537624192604809072081648408248748312500
810241228864512193536362880435456326592139968262441562500
92048276481658885806081306368195955219595521259712472392787327812500
10409661440414720165888043545607838208979776083980804723920157464023619639062500
118192135168101376045619201368576028740096431101444618944034642080173210405196312708588195312500
1216384294912243302412165120410572809853747217244057622170931220785248013856832062355744170061122125764976562500
133276863897657507843162931211860992032024678464049356896074035210808328969006940805404164482210794565526986463772924882812500
1465536137625613418496805109763321077769963233282241727488384296140850438868485043886848378291513620634082567737780961785641761913187624414062500
Technical details
Node id
n-2c87f8e68aebecbb · revision 0 · JSON
Definition source
derived:basis_map_A013610
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:    8,    12;
  2:   16,    48,     36;
  3:   32,   144,    216,    108;
  4:   64,   384,    864,    864,     324;
  5:  128,   960,   2880,   4320,    3240,     972;
  6:  256,  2304,   8640,  17280,   19440,   11664,    2916;
  7:  512,  5376,  24192,  60480,   90720,   81648,   40824,    8748;
  8: 1024, 12288,  64512, 193536,  362880,  435456,  326592,  139968,  26244;
  9: 2048, 27648, 165888, 580608, 1306368, 1959552, 1959552, 1259712, 472392, 78732;
%F Formula
The row polynomials satisfy (n-1)*P(n,x) = (2*n-2+(3*n-3)*x)*P(n-1,x) for n >= 2, with P(0,x) = 1, P(1,x) = 8 + 12*x.
%t Mathematica
P[0, x_] := 1;
P[1, x_] := 8 + 12*x;
P[n_, x_] := P[n, x] = Expand[Together[((2*n - 2 + (3*n - 3)*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] = 1; v[2] = 8 + 12*x; for(n = 2, N, my(i = n + 1); v[i] = ((2*n - 2 + (3*n - 3)*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.