A013618 → basis A013611

nonnegative coefficients only rational roots

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

Recurrence
\(P_{n}(x) = \left(12 + 44\,x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 144 + 1056\,x + 1936\,x^{2}\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9Pn(1)
0144105619363136
11728190086969685184175616
2207363041281672704408883237480969834496
3248832456192033454080122664960224885760164916224550731776
42985984656916486021734402943959040809588736011873968128725631385630840979456
53583180891968307210116513792618231398402266848460804987066613766095303639043192778096641727094849536
642998169612612796416161864220672118700428492854404363059201595861316403229257457467392306506697277441404822362521696717311574016
751597803521702727516162497333690368213660771287041175134242078724308825554288641053268468826112165513616529817615172081515233286181218395095045416169448144896

Computed in your browser ?

Technical details
Node id
n-314866308b34ea0d · revision 1 · JSON
Definition source
derived:basis_map_A013611
Fingerprint
f6-4f0d71d8efeb5cf0

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

OEIS matches ?

No OEIS matches.

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:          144,           1056,            1936;
  1:         1728,          19008,           69696,            85184;
  2:        20736,         304128,         1672704,          4088832,           3748096;
  3:       248832,        4561920,        33454080,        122664960,         224885760,          164916224;
  4:      2985984,       65691648,       602173440,       2943959040,        8095887360,        11873968128,         7256313856;
  5:     35831808,      919683072,     10116513792,      61823139840,      226684846080,       498706661376,       609530363904,        319277809664;
  6:    429981696,    12612796416,    161864220672,    1187004284928,     5440436305920,     15958613164032,     29257457467392,      30650669727744,      14048223625216;
  7:   5159780352,   170272751616,   2497333690368,   21366077128704,   117513424207872,    430882555428864,   1053268468826112,    1655136165298176,    1517208151523328,     618121839509504;
  8:  61917364224,  2270303354880,  37460005355520,  366275607920640,  2350268484157440,  10341181330292736,  31598054064783360,   66205446611927040,   91032489091399680,   74174620741140480,   27197360938418176;
  9: 743008370688, 29968004284416, 549413411880960, 6043547530690560, 44319348558397440, 227505989266440192, 834188627310280704, 2184779738193592320, 4005429520021585920, 4895524968915271680, 3590051643871199232, 1196683881290399744;
%F Formula
The row polynomials satisfy P(n,x) = (12+44*x)*P(n-1,x) for n >= 1, with P(0,x) = 144 + 1056*x + 1936*x^2.
%t Mathematica
P[0, x_] := 144 + 1056*x + 1936*x^2;
P[n_, x_] := P[n, x] = Expand[(12 + 44*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] = 144 + 1056*x + 1936*x^2; for(n = 1, N, my(i = n + 1); v[i] = (12 + 44*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-f283d143fa0950f0
  • 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-f283d143fa0950f0
  • 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-f283d143fa0950f0

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 (2)

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

References

  1. [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