basis-map coefficients of A113214, shifted → basis A013609 → basis A013609

palindromiconly rational roots

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

Recurrence

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

Rows ?

nx0x1x2x3x4x5x6x7Pn(1)
011
1-4-4-8
216321664
3-64-192-192-64-512
42561024153610242564096
5-1024-5120-10240-10240-5120-1024-32768
6409624576614408192061440245764096262144
7-16384-114688-344064-573440-573440-344064-114688-16384-2097152
Technical details
Node id
n-60d1035d9816e10d · revision 0 · JSON
Definition source
derived:basis_map_A013609
Fingerprint
f6-77a7ed3b1d5f257e

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: yes
  • 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:       1;
  1:      -4,       -4;
  2:      16,       32,       16;
  3:     -64,     -192,     -192,       -64;
  4:     256,     1024,     1536,      1024,       256;
  5:   -1024,    -5120,   -10240,    -10240,     -5120,     -1024;
  6:    4096,    24576,    61440,     81920,     61440,     24576,      4096;
  7:  -16384,  -114688,  -344064,   -573440,   -573440,   -344064,   -114688,   -16384;
  8:   65536,   524288,  1835008,   3670016,   4587520,   3670016,   1835008,   524288,    65536;
  9: -262144, -2359296, -9437184, -22020096, -33030144, -33030144, -22020096, -9437184, -2359296, -262144;
%F Formula
The row polynomials satisfy P(n,x) = -(4+4*x)*P(n-1,x) for n >= 1, with P(0,x) = 1.
%t Mathematica
P[0, x_] := 1;
P[n_, x_] := P[n, x] = Expand[-(4 + 4*x)*P[n - 1, x]];
Table[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten
%o PARI/GP
P(N) = {my(v = vector(N + 1)); v[1] = 1; for(n = 1, N, my(i = n + 1); v[i] = -(4 + 4*x)*v[i - 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.