A038336 → D

nonnegative coefficientsonly rational roots

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

Recurrence

\(\left(1 + n\right)\,P_{n}(x) = \left(24 + 20\,x + 12\,n + 10\,n x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 240 + 200\,x\)

Rows ?

nx0x1x2x3x4x5x6x7x8Pn(1)
0240200440
143207200300014520
26912017280014400040000425920
3103680034560004320000240000050000011712800
4149299206220800010368000086400000360000006000000309217920
52090188801045094400217728000024192000001512000000504000000700000007936593280
6286654464016721510400418037760005806080000048384000000241920000006720000000800000000199548631040
738698352640257989017600752467968000125411328000013063680000008709120000003628800000008640000000090000000004938828618240
Technical details
Node id
n-190c5af041de2688 · revision 0 · JSON
Definition source
derived:derivative
Fingerprint
f6-da2debf48cb6165b

Observed on the stored rows ?

  • Degrees: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 (affine: slope 1, intercept 1)
  • 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:           240,            200;
  1:          4320,           7200,            3000;
  2:         69120,         172800,          144000,           40000;
  3:       1036800,        3456000,         4320000,         2400000,          500000;
  4:      14929920,       62208000,       103680000,        86400000,        36000000,         6000000;
  5:     209018880,     1045094400,      2177280000,      2419200000,      1512000000,       504000000,        70000000;
  6:    2866544640,    16721510400,     41803776000,     58060800000,     48384000000,     24192000000,      6720000000,       800000000;
  7:   38698352640,   257989017600,    752467968000,   1254113280000,   1306368000000,    870912000000,    362880000000,     86400000000,     9000000000;
  8:  515978035200,  3869835264000,  12899450880000,  25082265600000,  31352832000000,  26127360000000,  14515200000000,   5184000000000,  1080000000000,   100000000000;
  9: 6810910064640, 56757583872000, 212840939520000, 472979865600000, 689762304000000, 689762304000000, 479001600000000, 228096000000000, 71280000000000, 13200000000000, 1100000000000;
%F Formula
The row polynomials satisfy (n+1)*P(n,x) = (12*n+24+(10*n+20)*x)*P(n-1,x) for n >= 1, with P(0,x) = 240 + 200*x.
%t Mathematica
P[0, x_] := 240 + 200*x;
P[n_, x_] := P[n, x] = Expand[Together[((12*n + 24 + (10*n + 20)*x)*P[n - 1, x])/(n + 1)]];
Table[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten
%o PARI/GP
P(N) = {my(v = vector(N + 1)); v[1] = 240 + 200*x; for(n = 1, N, my(i = n + 1); v[i] = ((12*n + 24 + (10*n + 20)*x)*v[i - 1])/(n + 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.