A130123 → (θ+1)² → basis A013610

nonnegative coefficientsonly rational roots

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

Recurrence

\(\left(n^{2}\right)\,P_{n}(x) = \left(2 + 6\,x + 4\,n + 12\,n x + 2\,n^{2} + 6\,n^{2} x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
011
182432
236216324576
31281152345634568192
44004800216004320032400102400
51152172801036803110404665602799361179648
6313656448423360169344038102404572288228614412845056
781921720321548288774144023224320418037764180377617915904134217728
8207364976645225472313528321175731202821754884232632323627970561360488961358954496
9512001382400165888001161216005225472001567641600313528320040310784003023308800100776960013421772800
1012390437171205018112040144896021076070407587385344189684633603251736576036582036480243880243207316407296129922760704
112949129732096145981440131383296078829977603310859059299325771776212840939520319261409280319261409280191556845568522427760641236950581248
12692224249200644111810564111810560277547212801332226621444662793175041199003959296224813242368029975098982402697758908416147150485913636787621478411613591568384
13160563262619648112715366412398690304929901772805021469573122008587829248602576348774413557967847424225966130790402711593569484822185765568512110928827842562559896027136107752139522048
1436864001548288003019161600362299392002988969984001793381990400807021895680027669322137600726319706112001452639412224002178959118336002377046310912001782784733184008228237230080017631936921600989560464998400
Technical details
Node id
n-11c42159a8aefb5d · revision 0 · JSON
Definition source
derived:basis_map_A013610
Fingerprint
f6-f9762973ec1089d7

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): 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 = 0, …, ascending powers of x
%e Example
Triangle begins:
  0:     1;
  1:     8,      24;
  2:    36,     216,      324;
  3:   128,    1152,     3456,      3456;
  4:   400,    4800,    21600,     43200,     32400;
  5:  1152,   17280,   103680,    311040,    466560,     279936;
  6:  3136,   56448,   423360,   1693440,   3810240,    4572288,    2286144;
  7:  8192,  172032,  1548288,   7741440,  23224320,   41803776,   41803776,   17915904;
  8: 20736,  497664,  5225472,  31352832, 117573120,  282175488,  423263232,  362797056,  136048896;
  9: 51200, 1382400, 16588800, 116121600, 522547200, 1567641600, 3135283200, 4031078400, 3023308800, 1007769600;
%F Formula
The row polynomials satisfy n^2*P(n,x) = (2*n^2+4*n+2+(6*n^2+12*n+6)*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[Together[((2*n^2 + 4*n + 2 + (6*n^2 + 12*n + 6)*x)*P[n - 1, x])/(n^2)]];
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] = ((2*n^2 + 4*n + 2 + (6*n^2 + 12*n + 6)*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 - 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.