A038328 → basis A013609 → basis A013610

nonnegative coefficientsonly rational roots

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

Recurrence

\(P_{n}(x) = \left(18 + 12\,x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 324 + 432\,x + 144\,x^{2}\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9Pn(1)
0324432144900
15832116647776172827000
210497627993627993612441620736810000
31889568629856083980805598720186624024883224300000
434012224136048896226748160201553920100776960268738562985984729000000
5612220032285702681657140536326348948480423263232016930529283762339843583180821870000000
6110199605765877312307213713728716818284971622415237476352081266540544270888468485159780352429981696656100000000
719835929036811901557422083173748645888493694233804849369423380483291294892032146279772979241794220851269657034752515978035219683000000000
Technical details
Node id
n-5b0a5a11faf67ad9 · revision 0 · JSON
Definition source
derived:basis_map_A013610
Fingerprint
f6-f06e51c139cfae05

Observed on the stored rows ?

  • Degrees: 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 (affine: slope 1, intercept 2)
  • 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:            324,             432,              144;
  1:           5832,           11664,             7776,             1728;
  2:         104976,          279936,           279936,           124416,            20736;
  3:        1889568,         6298560,          8398080,          5598720,          1866240,           248832;
  4:       34012224,       136048896,        226748160,        201553920,        100776960,         26873856,          2985984;
  5:      612220032,      2857026816,       5714053632,       6348948480,       4232632320,       1693052928,        376233984,         35831808;
  6:    11019960576,     58773123072,     137137287168,     182849716224,     152374763520,      81266540544,      27088846848,       5159780352,       429981696;
  7:   198359290368,   1190155742208,    3173748645888,    4936942338048,    4936942338048,    3291294892032,    1462797729792,     417942208512,     69657034752,     5159780352;
  8:  3570467226624,  23803114844160,   71409344532480,  126949945835520,  148108270141440,  118486616113152,   65825897840640,   25076532510720,   6269133127680,   928760463360,    61917364224;
  9: 64268410079232, 471301673914368, 1571005579714560, 3142011159429120, 4189348212572160, 3910058331734016, 2606705554489344, 1241288359280640, 413762786426880, 91947285872640, 12259638116352, 743008370688;
%F Formula
The row polynomials satisfy P(n,x) = (18+12*x)*P(n-1,x) for n >= 1, with P(0,x) = 324 + 432*x + 144*x^2.
%t Mathematica
P[0, x_] := 324 + 432*x + 144*x^2;
P[n_, x_] := P[n, x] = Expand[(18 + 12*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] = 324 + 432*x + 144*x^2; for(n = 1, N, my(i = n + 1); v[i] = (18 + 12*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. [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.