Real-rooted atlas

A013622 → basis A007318 → basis A007318

nonnegative coefficientsonly rational roots

Proved for all n all roots real, in (−∞, −1]coefficients of one signHadamard kernelinterlacing (weak)

Recurrence

\(P_{n}(x) = \left(13 + 5\,x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
011
113518
216913025324
3219725359751255832
42856143940253506500625104976
53712937140255492502112504062531251889568
648268091113879010710375549250015843752437501562534012224
7627485171689383151949288251249543754805937511090625142187578125612220032
8815730721250994068033787663002599051000124954375038447500073937500812500039062511019960576
91060449937336707882445564736653005068149450029239323750112458937502883562500475312500457031251953125198359290368
101378584918495302249686509176970611259412277550006335186812502923932375009371578125020596875000297070312525390625097656253570467226624
1117921603940377582217051695145811866378751682444612062512941881631250696870549375026802713437507363382812501416035156251815429687513964843754882812564268410079232
12232980851224811075296236422202274665115508502916237327575002523666918093751553025795750006968705493750022973754375000552253710937594402343750010892578125076171875002441406251156831381426176
1330287510659225315143755329612653494712768372150492844108360175047388856573093753280766993521875168244461206250064709408156250018666175429687539884990234375613615234375064365234375041259765625122070312520822964865671168
14393737638569928921201257461457710530031436536442758154329792868350086247718963030625663443992023312503827561492442187516824446120625000566207321367187514518136445312502791949316406253904824218750037546386718752221679687506103515625374813367582081024
Technical details
Node id
n-d71ddb17f4c0ce20 · revision 0 · JSON
Definition source
derived:shift_x_plus_one
Fingerprint
f6-3dee56618ab9ea64

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:          13,           5;
  2:         169,         130,          25;
  3:        2197,        2535,         975,         125;
  4:       28561,       43940,       25350,        6500,         625;
  5:      371293,      714025,      549250,      211250,       40625,        3125;
  6:     4826809,    11138790,    10710375,     5492500,     1584375,      243750,      15625;
  7:    62748517,   168938315,   194928825,   124954375,    48059375,    11090625,    1421875,     78125;
  8:   815730721,  2509940680,  3378766300,  2599051000,  1249543750,   384475000,   73937500,   8125000,   390625;
  9: 10604499373, 36707882445, 56473665300, 50681494500, 29239323750, 11245893750, 2883562500, 475312500, 45703125, 1953125;
%F Formula
The row polynomials satisfy P(n,x) = (13+5*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[(13 + 5*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] = (13 + 5*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. [ASW52] Michael Aissen, I. J. Schoenberg and A. M. Whitney. On the generating functions of totally positive sequences I. Journal d’Analyse Mathématique, 2(1):93–103, 1952. doi:10.1007/BF02786970
  2. [AW24] Christos A. Athanasiadis and David G. Wagner. Veronese sections and interlacing matrices of polynomials and formal power series. arXiv:2404.12989. arXiv
  3. [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
  4. [Bra15] Petter Brändén. Unimodality, log-concavity, real-rootedness and beyond. Handbook of enumerative combinatorics, :437–483, March 2015. doi:10.1201/b18255-10
  5. [Edr53] Albert Edrei. Proof of a Conjecture of Schoenberg on the Generating Function of a Totally Positive Sequence. Canadian Journal of Mathematics, 5:86–94, 1953. doi:10.4153/CJM-1953-010-3
  6. [LW07] Lily L. Liu and Yi Wang. A unified approach to polynomial sequences with only real zeros. Advances in Applied Mathematics, 38(4):542–560, May 2007. doi:10.1016/j.aam.2006.02.003
  7. [SP14] J Schur and G Polya. Über zwei Arten von Faktorenfolgen in der Theorie der algebraischen Gleichungen. J. Reine Angew. Math., 1914.