basis-map coefficients of A030528, shifted → basis A013609 → basis A013609

only rational roots

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

Recurrence

\(P_{n}(x) = \left(-3 - 4\,x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
011
1-3-4-7
29241649
3-27-108-144-64-343
4814328647682562401
5-243-1620-4320-5760-3840-1024-16807
67295832194403456034560184324096117649
7-2187-20412-81648-181440-241920-193536-86016-16384-823543
8656169984326592870912145152015482881032192393216655365764801
9-19683-236196-1259712-3919104-7838208-10450944-9289728-5308416-1769472-262144-40353607
1059049787320472392016796160391910406270566469672960530841602654208078643201048576282475249
11-177147-2598156-17321040-69284160-184757760-344881152-459841536-437944320-291962880-129761280-34603008-4194304-1977326743
12531441850305662355744277136640831409920177367449627590492163153199104262766592015571353606228541441509949441677721613841287201
13-1594323-27634932-221079456-1080832896-3602776320-8646663168-15371845632-20495794176-20495794176-15182069760-8097103872-2944401408-654311424-67108864-96889010407
1447829698928208877377809641268165121513166054440351094784807021895681229747650561434705592321275293859848501959065641221619712137405399042818572288268435456678223072849
Technical details
Node id
n-9e75df4a9edf89e2 · revision 0 · JSON
Definition source
derived:basis_map_A013609
Fingerprint
f6-c91d5d506c107735

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:     -3,      -4;
  2:      9,      24,       16;
  3:    -27,    -108,     -144,      -64;
  4:     81,     432,      864,      768,      256;
  5:   -243,   -1620,    -4320,    -5760,    -3840,     -1024;
  6:    729,    5832,    19440,    34560,    34560,     18432,     4096;
  7:  -2187,  -20412,   -81648,  -181440,  -241920,   -193536,   -86016,   -16384;
  8:   6561,   69984,   326592,   870912,  1451520,   1548288,  1032192,   393216,    65536;
  9: -19683, -236196, -1259712, -3919104, -7838208, -10450944, -9289728, -5308416, -1769472, -262144;
%F Formula
The row polynomials satisfy P(n,x) = -(3+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[-(3 + 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] = -(3 + 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.