A136572 → basis A013610

nonnegative coefficients only rational roots

Proved for all n: all roots real, in (−∞, 0] · coefficients of one sign · Hadamard kernel what this means

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

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
011
1134
22121832
3654162162384
4242881296259219446144
5120180010800324004860029160122880
6720129609720038880087480010497605248802949120
7504010584095256047628001428840025719120257191201102248082575360
84032096768010160640609638402286144005486745608230118407054387202645395202642411520
93628809797760117573120823011840370355328011110659840222213196802857026816021427701120714256704095126814720
1036288001088640001469664000117573120006172588800022221319680055553299200095234227200010713850560007142567040002142770112003805072588800
11399168001317254400197588160001778293440001066976064000448129946880013443898406400288083537280004321253059200043212530592000259275183552007071141369600167423193907200
12479001600172440576002845269504002845269504000192055691520009218673192960032265356175360082968058736640015556511013120002074201468416000186678132157440010182443572224002545610893056008036313307545600
1362270208002428538112004371368601600480850546176003606379096320001947444712012800778977884805120023369336544153600525810072243456008763501204057600010516201444869120086041648185292800430208240926464009927882482918400417888291992371200
148717829120036614882304007139902049280085678824591360070685030287872004241101817272320019084958177725440065434142323630080017176462359952896003435292471990579200515293870798586880056213876814391296004216040761079347200194586496665200640041697106428257280023401744351572787200

Generated b-files: A047053 (row sums) ?

Computed in your browser ?

Technical details
Node id
n-412b54b3d1f71393 · revision 1 · JSON
Definition source
derived:basis_map_A013610
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

OEIS matches ?

A generated b-file is computed from the node's definition along the row alignment of its OEIS link and starts at the entry's offset. It is an identification on a finite prefix, not a proof that the node and the OEIS entry agree for every n.

OEIS submission text ?

Fields to paste into an OEIS submission: the example %e, the formula %F and programs %t (Mathematica) and %o (PARI/GP) that list the same rows. For an OEIS link the row numbers, the offset and the orientation are those of the entry, as matched; the matched terms were compared with the published ones, which identifies the node with the entry on a finite prefix, not for every n. The PARI/GP program is not machine-checked here.

The atlas's own rows: n = 0, …, ascending powers of x
%e Example
Triangle begins:
  0:      1;
  1:      1,       3;
  2:      2,      12,        18;
  3:      6,      54,       162,       162;
  4:     24,     288,      1296,      2592,       1944;
  5:    120,    1800,     10800,     32400,      48600,       29160;
  6:    720,   12960,     97200,    388800,     874800,     1049760,      524880;
  7:   5040,  105840,    952560,   4762800,   14288400,    25719120,    25719120,    11022480;
  8:  40320,  967680,  10160640,  60963840,  228614400,   548674560,   823011840,   705438720,   264539520;
  9: 362880, 9797760, 117573120, 823011840, 3703553280, 11110659840, 22221319680, 28570268160, 21427701120, 7142567040;
%F Formula
The row polynomials satisfy P(n,x) = (n+3*n*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[(n + 3*n*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] = 1; for(n = 1, N, my(i = n + 1); v[i] = (n + 3*n*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)

Generated with polytool c48629374597.

Proved properties

  • Real-rooted. Every row P_n, n >= 0, is zero or real-rooted with all roots in (-inf, 0]
    Every polynomial of the sequence has only real roots, inside the stated interval.
    by the cited steps: e-77bf2cb365051314
  • Coefficients of one sign. Every nonzero row, n >= 0: the coefficients of P_n have one sign
    All coefficients of each polynomial have the same sign (after x -> -x when alternating).
    derived from the cited steps by a stated theorem: e-77bf2cb365051314
  • Hadamard kernel (Malo). Rows P_n, n >= 0, are Hadamard kernels (preserve real-rootedness)
    Multiplying the coefficients of any real-rooted polynomial termwise by those of a row (Hadamard product) gives a real-rooted polynomial again.
    derived from the cited steps by a stated theorem: e-77bf2cb365051314

Proof chains

1 incoming proof step. Each step is expanded back to the roots of the proof DAG, the theorem checks of a node's own rule. JSON

Same fingerprint (16)

Equal up to content, sign, reversal and a small index shift.