A178822 → x ↦ x+1 → x ↦ x+1

nonnegative coefficientsonly rational roots

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

Recurrence

\(\left(n\right)\,P_{n}(x) = \left(15 + 5\,x + 3\,n + n x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
011
118624
218912621336
315121512504563584
410206136086804151212632256
56123610206068040226803780252258048
63367986735965613302494806237083164621892352
717321044041576404157622453207484401496881663279212976128
884440072251735226270244175134967297290194594432432430888128784344832
93940536611821609815762146412259447261297236204324124540536648648540542002524812288
1017732414759108049088662073578810732045972927018389170851081030972972012162159009030033148873728
1177377809628371863524728643920472864392031524292801471133664490377888116756640194594402162160144144436818320719872
1232885569081315422763224116083992267956488802009673666010718259552416821204811909177282481078603675672036756722227686188103817412608
13136601594645919402434411838804868814469650395212058041996072348251976321547786561071825955226795648884962157206616209660147363341528568574988746752
1455616363532259543029816562343231268749790975024687308393772458205595848229102797924872772563522545586643656568592089428098681142799849523332488376116283121367482368
Technical details
Node id
n-f4c2bb27966c279d · revision 0 · JSON
Definition source
derived:shift_x_plus_one
Fingerprint
f6-f9762973ec1089d7

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:       18,         6;
  2:      189,       126,        21;
  3:     1512,      1512,       504,        56;
  4:    10206,     13608,      6804,      1512,      126;
  5:    61236,    102060,     68040,     22680,     3780,      252;
  6:   336798,    673596,    561330,    249480,    62370,     8316,     462;
  7:  1732104,   4041576,   4041576,   2245320,   748440,   149688,   16632,    792;
  8:  8444007,  22517352,  26270244,  17513496,  7297290,  1945944,  324324,  30888,  1287;
  9: 39405366, 118216098, 157621464, 122594472, 61297236, 20432412, 4540536, 648648, 54054, 2002;
%F Formula
The row polynomials satisfy n*P(n,x) = (3*n+15+(n+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[Together[((3*n + 15 + (n + 5)*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 + (n + 5)*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.