basis-map coefficients of A113214, shifted → basis A013609 → basis A013611

only rational roots

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

Recurrence

\(P_{n}(x) = \left(-4 - 8\,x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)

Rows ?

nx0x1x2x3x4x5x6x7Pn(1)
011
1-4-8-12
2166464144
3-64-384-768-512-1728
4256204861448192409620736
5-1024-10240-40960-81920-81920-32768-248832
64096491522457606553609830407864322621442985984
7-16384-229376-1376256-4587520-9175040-11010048-7340032-2097152-35831808
Technical details
Node id
n-7a7b1ea2b00dadf1 · revision 0 · JSON
Definition source
derived:basis_map_A013611
Fingerprint
f6-11aec07ce60b6d61

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: 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:       1;
  1:      -4,       -8;
  2:      16,       64,        64;
  3:     -64,     -384,      -768,       -512;
  4:     256,     2048,      6144,       8192,       4096;
  5:   -1024,   -10240,    -40960,     -81920,     -81920,      -32768;
  6:    4096,    49152,    245760,     655360,     983040,      786432,      262144;
  7:  -16384,  -229376,  -1376256,   -4587520,   -9175040,   -11010048,    -7340032,    -2097152;
  8:   65536,  1048576,   7340032,   29360128,   73400320,   117440512,   117440512,    67108864,   16777216;
  9: -262144, -4718592, -37748736, -176160768, -528482304, -1056964608, -1409286144, -1207959552, -603979776, -134217728;
%F Formula
The row polynomials satisfy P(n,x) = -(4+8*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 + 8*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 + 8*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.