basis-map coefficients of A030528, shifted → D → basis A013610

only rational roots

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

Recurrence

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

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13Pn(1)
00
1-1-1
2268
3-3-18-27-48
4436108108256
5-5-60-270-540-405-1280
66905401620243014586144
7-7-126-945-3780-8505-10206-5103-28672
881681512756022680408244082417496131072
9-9-216-2268-13608-51030-122472-183708-157464-59049-589824
10102703240226801020603061806123607873205904901968302621440
11-11-330-4455-35640-187110-673596-1683990-2886840-3247695-2165130-649539-11534336
121239659405346032076013471924041576866052012990780129907807794468212576450331648
13-13-468-7722-77220-521235-2501928-8756748-22517352-42220035-56293380-50664042-27634932-6908733-218103808
14145469828108108810810437837417513496525404881182160981970268302364321961934445249672226222320522939524096
Technical details
Node id
n-9210b444f37f545f · revision 0 · JSON
Definition source
derived:basis_map_A013610
Fingerprint
f6-f9762973ec1089d7

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:  2,    6;
  3: -3,  -18,   -27;
  4:  4,   36,   108,    108;
  5: -5,  -60,  -270,   -540,   -405;
  6:  6,   90,   540,   1620,   2430,    1458;
  7: -7, -126,  -945,  -3780,  -8505,  -10206,   -5103;
  8:  8,  168,  1512,   7560,  22680,   40824,   40824,   17496;
  9: -9, -216, -2268, -13608, -51030, -122472, -183708, -157464, -59049;
%F Formula
The row polynomials satisfy (n-1)*P(n,x) = -(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[(-(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] = (-(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.