A178822 → basis A013611 → D

nonnegative coefficientsonly rational roots

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

Recurrence

\(\left(-1 + n\right)\,P_{n}(x) = \left(10 + 20\,x + 2\,n + 4\,n x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 0\)
\(P_{1}(x) = 24\)

Rows ?

nx0x1x2x3x4x5x6Pn(1)
00
12424
23366721008
32688107521075224192
41612896768193536129024435456
5806406451201935360258048012902406531840
635481635481601419264028385280283852801135411286220288
714192641703116885155840227082240340623360272498688908328961034643456
Technical details
Node id
n-f4b4db1dfdb62066 · revision 0 · JSON
Definition source
derived:derivative
Fingerprint
f6-11aec07ce60b6d61

Observed on the stored rows ?

  • Degrees: -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 (affine: slope 1, intercept -1)
  • 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:        0;
  1:       24;
  2:      336,       672;
  3:     2688,     10752,      10752;
  4:    16128,     96768,     193536,     129024;
  5:    80640,    645120,    1935360,    2580480,     1290240;
  6:   354816,   3548160,   14192640,   28385280,    28385280,    11354112;
  7:  1419264,  17031168,   85155840,  227082240,   340623360,   272498688,    90832896;
  8:  5271552,  73801728,  442810368, 1476034560,  2952069120,  3542482944,  2361655296,   674758656;
  9: 18450432, 295206912, 2066448384, 8265793536, 20664483840, 33063174144, 33063174144, 18893242368, 4723310592;
%F Formula
The row polynomials satisfy (n-1)*P(n,x) = (2*n+10+(4*n+20)*x)*P(n-1,x) for n >= 2, with P(0,x) = 0, P(1,x) = 24.
%t Mathematica
P[0, x_] := 0;
P[1, x_] := 24;
P[n_, x_] := P[n, x] = Expand[Together[((2*n + 10 + (4*n + 20)*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] = 0; v[2] = 24; for(n = 2, N, my(i = n + 1); v[i] = ((2*n + 10 + (4*n + 20)*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.