A178822 → x ↦ x+1 → basis A013610

palindromicγ-positivenonnegative coefficientsonly rational roots

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

Recurrence

\(\left(n\right)\,P_{n}(x) = \left(15 + 15\,x + 3\,n + 3\,n x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
011
1181836
2189378189756
3151245364536151212096
41020640824612364082410206163296
561236306180612360612360306180612361959552
63367982020788505197067359605051970202078833679821555072
717321041212472836374184606236406062364036374184121247281732104221709312
88444007675520562364321964728643925910804904728643922364321966755205684440072161665792
9394053663546482941418593176331005074449650761164965076116331005074414185931763546482943940536620175547392
1017732414717732414707979586615212788976403723807087044685685044372380708702127889764079795866151773241470177324147181579926528
117737780968511559056425577952801276733858402553467716803574854803523574854803522553467716801276733858404255779528085115590567737780961584697540608
123288556908394626828962170447559287234825197601627835669460260453707113630386265829922604537071136162783566946072348251976021704475592839462682896328855690813469929095168
13136601594641775820730321065492438192390680560670497670140167601758062523016823440833640224234408336402241758062523016897670140167603906805606704106549243819217758207303213660159464111904026329088
1455616363532778629089448506108908141220244356325648556719798955321113439597910641670159396865961908753596418241670159396865961113439597910645567197989553220244356325648506108908141277862908944855616363532911218500108288
Technical details
Node id
n-67948e785b03de0c · revision 0 · JSON
Definition source
derived:basis_map_A013610
Fingerprint
f6-77a7ed3b1d5f257e

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: yes
  • γ-positive (gamma_positive): yes
  • 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:       18,        18;
  2:      189,       378,        189;
  3:     1512,      4536,       4536,       1512;
  4:    10206,     40824,      61236,      40824,      10206;
  5:    61236,    306180,     612360,     612360,     306180,      61236;
  6:   336798,   2020788,    5051970,    6735960,    5051970,    2020788,     336798;
  7:  1732104,  12124728,   36374184,   60623640,   60623640,   36374184,   12124728,    1732104;
  8:  8444007,  67552056,  236432196,  472864392,  591080490,  472864392,  236432196,   67552056,   8444007;
  9: 39405366, 354648294, 1418593176, 3310050744, 4965076116, 4965076116, 3310050744, 1418593176, 354648294, 39405366;
%F Formula
The row polynomials satisfy n*P(n,x) = (3*n+15+(3*n+15)*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 + 15 + (3*n + 15)*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 + 15 + (3*n + 15)*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.