basis-map coefficients of A026729 → basis A056242 → x ↦ x+1

nonnegative coefficients

Proved for all n: all roots real, in (−∞, −1] · coefficients of one sign · Hadamard kernel what this means

Recurrence
\(\left(-1 + n\right)\,P_{n}(x) = \left(1 + 2\,x + n\right)\,P_{n-1}(x) + \left(4 + 6\,x + 2\,x^{2}\right)\,P_{n-1}'(x)\)
\(P_{1}(x) = 1\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
111
2325
31013427
43465408147
511629226910816801
639612361515914272324365
7135250367702620127766566423787
846161998036614368652204878401536128129627
9157607772816597620058415016971368210403520256706401
105380829785672615210239449208835480822159845436879365123849525
1118371211278243090640498093652304983741189184665262136013644817664102420977947
126272324229200128680482333098428018154234087051388893658540241718272334592389122048114319107
13214150415731904526214881060075201432926521369582529493866148104596176868804603136805120849924096622980801
147311552581249922119844644697430407058183567595827486024845713566987221576661445139884812014336190720018432081923394927485
15249632002135177608432129602038304560337016668040327585483602268206244061617712605836644940345281446416643068236844584963973121638418500622507

Generated b-files: A158869 (row sums) ?

Computed in your browser ?

Technical details
Node id
n-2779422d3a9a18c1 · revision 1 · JSON
Definition source
derived:shift_x_plus_one
Fingerprint
f6-cbe7d293337761ab

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 -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): no

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 = 1, …, ascending powers of x
%e Example
Triangle begins:
   1:     1;
   2:     3,      2;
   3:    10,     13,      4;
   4:    34,     65,     40,       8;
   5:   116,    292,    269,     108,     16;
   6:   396,   1236,   1515,     914,    272,     32;
   7:  1352,   5036,   7702,    6201,   2776,    656,     64;
   8:  4616,  19980,  36614,   36865,  22048,   7840,   1536,   128;
   9: 15760,  77728, 165976,  200584, 150169,  71368,  21040,  3520,  256;
  10: 53808, 297856, 726152, 1023944, 920883, 548082, 215984, 54368, 7936, 512;
%F Formula
The row polynomials satisfy (n-1)*P(n,x) = (n+1+2*x)*P(n-1,x) + (4+6*x+2*x^2)*d/dx P(n-1,x) for n >= 2, with P(1,x) = 1.
%t Mathematica
P[1, x_] := 1;
P[n_, x_] := P[n, x] = Expand[Together[((n + 1 + 2*x)*P[n - 1, x] + (4 + 6*x + 2*x^2)*D[P[n - 1, x], x])/(n - 1)]];
Table[CoefficientList[P[n, x], x], {n, 1, 10}] // Flatten
%o PARI/GP
P(N) = {my(v = vector(N)); v[1] = 1; for(n = 2, N, my(i = n); v[i] = ((n + 1 + 2*x)*v[i - 1] + (4 + 6*x + 2*x^2)*deriv(v[i - 1], x))/(n - 1)); v};
row(n, p) = {my(c = Vecrev(p)); c};
T(N) = {my(v = P(N)); concat(vector(#v, i, row(i, v[i])))};
T(10)

Generated with polytool c48629374597.

Proved properties

  • Real-rooted. Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, -1]
    Every polynomial of the sequence has only real roots, inside the stated interval.
    by the cited steps: e-e8893cf05feee942
  • Coefficients of one sign. Every nonzero row, n >= 1: 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-e8893cf05feee942
  • Hadamard kernel (Malo). Rows P_n, n >= 1, 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-e8893cf05feee942

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

No candidate equalities or related sequences.