basis-map coefficients of A113214, shifted → D → basis A013610

only rational roots

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

Recurrence

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

Rows ?

nx0x1x2x3x4x5x6Pn(1)
00
1-1-1
24610
3-12-36-27-75
432144216108500
5-80-480-1080-1080-405-3125
61921440432064804860145818750
7-448-4032-15120-30240-34020-20412-5103-109375
Technical details
Node id
n-17feb40af89fa354 · revision 0 · JSON
Definition source
derived:basis_map_A013610
Fingerprint
f6-f06e51c139cfae05

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): no
  • 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:    -1;
  2:     4,      6;
  3:   -12,    -36,     -27;
  4:    32,    144,     216,     108;
  5:   -80,   -480,   -1080,   -1080,    -405;
  6:   192,   1440,    4320,    6480,    4860,    1458;
  7:  -448,  -4032,  -15120,  -30240,  -34020,  -20412,   -5103;
  8:  1024,  10752,   48384,  120960,  181440,  163296,   81648,   17496;
  9: -2304, -27648, -145152, -435456, -816480, -979776, -734832, -314928, -59049;
%F Formula
The row polynomials satisfy (n-1)*P(n,x) = -(2*n+3*n*x)*P(n-1,x) for n >= 2, with P(0,x) = 0, P(1,x) = -1.
%t Mathematica
P[0, x_] := 0;
P[1, x_] := -1;
P[n_, x_] := P[n, x] = Expand[Together[(-(2*n + 3*n*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] = -1; for(n = 2, N, my(i = n + 1); v[i] = (-(2*n + 3*n*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. [SP14] J Schur and G Polya. Über zwei Arten von Faktorenfolgen in der Theorie der algebraischen Gleichungen. J. Reine Angew. Math., 1914.