basis-map coefficients of A026729, shifted → basis A007318 → basis A013609

palindromiconly rational roots

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

Recurrence

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

Rows ?

nx0x1x2x3x4x5x6x7Pn(1)
111
2-2-2-4
348416
4-8-24-24-8-64
51664966416256
6-32-160-320-320-160-32-1024
7643849601280960384644096
8-128-896-2688-4480-4480-2688-896-128-16384
Technical details
Node id
n-0d923441cf35836a · 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 -1)
  • 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 = 1, …, ascending powers of x
%e Example
Triangle begins:
   1:    1;
   2:   -2,    -2;
   3:    4,     8,      4;
   4:   -8,   -24,    -24,     -8;
   5:   16,    64,     96,     64,     16;
   6:  -32,  -160,   -320,   -320,   -160,    -32;
   7:   64,   384,    960,   1280,    960,    384,     64;
   8: -128,  -896,  -2688,  -4480,  -4480,  -2688,   -896,   -128;
   9:  256,  2048,   7168,  14336,  17920,  14336,   7168,   2048,   256;
  10: -512, -4608, -18432, -43008, -64512, -64512, -43008, -18432, -4608, -512;
%F Formula
The row polynomials satisfy P(n,x) = -(2+2*x)*P(n-1,x) for n >= 2, with P(1,x) = 1.
%t Mathematica
P[1, x_] := 1;
P[n_, x_] := P[n, x] = Expand[-(2 + 2*x)*P[n - 1, x]];
Table[CoefficientList[P[n, x], x], {n, 1, 10}] // Flatten
%o PARI/GP
P(N) = {my(v = vector(N)); v[1] = 1; for(n = 2, N, my(i = n); v[i] = -(2 + 2*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, v[i])))};
T(10)

polytool c48629374597

Properties

Proof chains ? JSON

Same fingerprint ?