A136572 → D → basis A013610

nonnegative coefficientsonly rational roots

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

Recurrence

\(\left(-1 + n\right)\,P_{n}(x) = \left(n^{2} + 3\,n^{2} x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 0\)
\(P_{1}(x) = 1\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13Pn(1)
00
111
241216
318108162288
496864259225926144
56007200324006480048600153600
64320648003888001166400174960010497604423680
735280635040476280019051200428652005143824025719120144506880
8322560677376060963840304819200914457600164602368016460236807054387205284823040
932659207838208082301184049380710401851776640044442639360666639590405714053632021427701120214035333120
1036288000979776000117573120008230118400037035532800011110659840002222131968000285702681600021427701120007142567040009512681472000
11439084800131725440001778293440001422634752000746883244800026887796812800672194920320001152334149120001296375917760008642506118400025927518355200460413783244800
12574801920018968463360028452695040002560742553600015364455321600064530712350720019359213705216004148402936832000622260440524800062226044052480003733562643148800101824435722240024108939922636800
138095127040029142457344004808505461760048085054617600032457411866880001557955769610240054528451936358400140216019264921600262905036121728000350540048162304000315486043346073600172083296370585600430208240926464001358136948975206400
1412204960768004759934699520085678824591360094246707050496007068503028787200038169916355450880015267966542180352004580389962654105600103058774159717376001717646235995289600020611754831943475200168641630443173888008432081522158694400194586496665200640081906105230504755200
Technical details
Node id
n-3fe38ff3b2e587dc · revision 0 · JSON
Definition source
derived:basis_map_A013610
Fingerprint
f6-f9762973ec1089d7

Observed on the stored rows ?

  • Degrees: -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 (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:       0;
  1:       1;
  2:       4,       12;
  3:      18,      108,       162;
  4:      96,      864,      2592,       2592;
  5:     600,     7200,     32400,      64800,       48600;
  6:    4320,    64800,    388800,    1166400,     1749600,     1049760;
  7:   35280,   635040,   4762800,   19051200,    42865200,    51438240,    25719120;
  8:  322560,  6773760,  60963840,  304819200,   914457600,  1646023680,  1646023680,   705438720;
  9: 3265920, 78382080, 823011840, 4938071040, 18517766400, 44442639360, 66663959040, 57140536320, 21427701120;
%F Formula
The row polynomials satisfy (n-1)*P(n,x) = (n^2+3*n^2*x)*P(n-1,x) for n >= 2, with P(0,x) = 0, P(1,x) = 1.
%t Mathematica
P[0, x_] := 0;
P[1, x_] := 1;
P[n_, x_] := P[n, x] = Expand[Together[((n^2 + 3*n^2*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] = 0; v[2] = 1; for(n = 2, N, my(i = n + 1); v[i] = ((n^2 + 3*n^2*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. [SP14] J Schur and G Polya. Über zwei Arten von Faktorenfolgen in der Theorie der algebraischen Gleichungen. J. Reine Angew. Math., 1914.