basis-map coefficients of A026729 → D → basis A013611

nonnegative coefficientsonly rational roots

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

Recurrence

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

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13Pn(1)
10
211
32810
43244875
5448192256500
6580480128012803125
7612096038407680614418750
8716816808960268804300828672109375
9822426881792071680172032229376131072625000
109288403232256161280516096103219211796485898243515625
11103605760537603225601290240344064058982405898240262144019531250
12114407920844805913602838528946176021626880324403202883584011534336107421875
13125281056012672010137605677056227082246488064012976128017301504013841203250331648585937500
141362413728183040164736010543104492011521686896644217241607497318408996782086543114242181038083173828125
151472817472256256256256018450432984023043936092161180827648262406144041984983044580179968305345331293952409617089843750
Technical details
Node id
n-8dae71118319cf76 · revision 0 · JSON
Definition source
derived:basis_map_A013611
Fingerprint
f6-03d7b8417365c509

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 -2)
  • 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 = 1, …, ascending powers of x
%e Example
Triangle begins:
   1: 0;
   2: 1;
   3: 2,   8;
   4: 3,  24,   48;
   5: 4,  48,  192,   256;
   6: 5,  80,  480,  1280,   1280;
   7: 6, 120,  960,  3840,   7680,   6144;
   8: 7, 168, 1680,  8960,  26880,  43008,   28672;
   9: 8, 224, 2688, 17920,  71680, 172032,  229376,  131072;
  10: 9, 288, 4032, 32256, 161280, 516096, 1032192, 1179648, 589824;
%F Formula
The row polynomials satisfy (n-2)*P(n,x) = (n-1+(4*n-4)*x)*P(n-1,x) for n >= 3, with P(1,x) = 0, P(2,x) = 1.
%t Mathematica
P[1, x_] := 0;
P[2, x_] := 1;
P[n_, x_] := P[n, x] = Expand[Together[((n - 1 + (4*n - 4)*x)*P[n - 1, x])/(n - 2)]];
Table[CoefficientList[P[n, x], x], {n, 1, 10}] // Flatten
%o PARI/GP
P(N) = {my(v = vector(N)); v[1] = 0; v[2] = 1; for(n = 3, N, my(i = n); v[i] = ((n - 1 + (4*n - 4)*x)*v[i - 1])/(n - 2)); v};
row(n, p) = {my(c = Vecrev(p)); c};
T(N) = {my(v = P(N)); concat(vector(#v, i, row(i, v[i])))};
T(10)

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.