A178821 → basis A007318 → basis A013611

nonnegative coefficientsonly rational roots

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

Recurrence

\(\left(n\right)\,P_{n}(x) = \left(12 + 16\,x + 3\,n + 4\,n x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
011
1152035
2135360240735
394537805040224012005
4567030240604805376017920168070
5306182041205443207257604838401290242117682
61530901224720408240072576007257600387072086016024706290
7721710673596026943840598752007983360063866880283852805406720271769190
8324769534642080161663040431101440718502400766402560510935040194641920324403202853576495
91407334516888014090069408028021593605604318720747242496066421555203795517440126517248018743296028852829005
1059108049788107320472864392016812956160392302310406276836966469742632960531372441602656862208078721843201049624576282757724249
11241805655354648294023643219600945728784002521943424004707627724806276836966405977939968003985293312001771241472004723310592057252249602699051004195
129672226201547556192011348745408050438868480015131660544003228087582720502146957312057388223692804782351974400283398635520011335945420802748107980803053453312025191142705820
133794488740657711381605261691052802572382292480857460764160020579058339840365849926041604877999013888048779990138880361333260288001927110721536070076753510401557261189120159719096320230595844768660
1414635885140273203189280236776097376012628058526720463028812646401234743500390402469487000780803763027810713604390199112499203902399211110402601599474073601261381563187204204605210624086248312012808214124953602075362602917940
Technical details
Node id
n-ff7ffad3707bcd4d · revision 0 · JSON
Definition source
derived:basis_map_A013611
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): 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:       15,        20;
  2:      135,       360,       240;
  3:      945,      3780,      5040,       2240;
  4:     5670,     30240,     60480,      53760,      17920;
  5:    30618,    204120,    544320,     725760,     483840,     129024;
  6:   153090,   1224720,   4082400,    7257600,    7257600,    3870720,     860160;
  7:   721710,   6735960,  26943840,   59875200,   79833600,   63866880,   28385280,    5406720;
  8:  3247695,  34642080, 161663040,  431101440,  718502400,  766402560,  510935040,  194641920,   32440320;
  9: 14073345, 168880140, 900694080, 2802159360, 5604318720, 7472424960, 6642155520, 3795517440, 1265172480, 187432960;
%F Formula
The row polynomials satisfy n*P(n,x) = (3*n+12+(4*n+16)*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[((3*n + 12 + (4*n + 16)*x)*P[n - 1, x])/(n)]];
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*n + 12 + (4*n + 16)*x)*v[i - 1])/(n)); 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. [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
  4. [SP14] J Schur and G Polya. Über zwei Arten von Faktorenfolgen in der Theorie der algebraischen Gleichungen. J. Reine Angew. Math., 1914.