A103633 → D
nonnegative coefficients only rational roots
Proved for all n: all roots real, in (−∞, 0] · coefficients of one sign · Hadamard kernel what this means
Rows ?
| n | x0 | x1 | x2 | x3 | x4 | x5 | x6 | Pn(1) |
|---|---|---|---|---|---|---|---|---|
| 0 | 0 | |||||||
| 1 | 1 | 1 | ||||||
| 2 | 1 | 2 | 3 | |||||
| 3 | 0 | 2 | 3 | 5 | ||||
| 4 | 0 | 2 | 6 | 4 | 12 | |||
| 5 | 0 | 0 | 3 | 8 | 5 | 16 | ||
| 6 | 0 | 0 | 3 | 12 | 15 | 6 | 36 | |
| 7 | 0 | 0 | 0 | 4 | 15 | 18 | 7 | 44 |
Generated b-files: A203150 (row sums) ?
Computed in your browser ?
Technical details
- Node id
n-8d06c768dd7b6bf3· revision 1 · JSON- Definition source
derived:derivative- Fingerprint
f6-fa800db18f277715
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
OEIS matches ?
- A203150: row sums, 14 terms agree OEIS nonn (row-sum match: finite agreement only) · view at the OEIS · generated b-file 200 terms from n = 1 ?
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 ExampleTriangle begins: 0: 0; 1: 1; 2: 1, 2; 3: 0, 2, 3; 4: 0, 2, 6, 4; 5: 0, 0, 3, 8, 5; 6: 0, 0, 3, 12, 15, 6; 7: 0, 0, 0, 4, 15, 18, 7; 8: 0, 0, 0, 4, 20, 36, 28, 8; 9: 0, 0, 0, 0, 5, 24, 42, 32, 9;
%F FormulaThe row polynomials satisfy (n^2-n+(4*n^2-10*n+6)*x+(4*n^2-12*n+8)*x^2)*P(n,x) = -(n^3-4*n^2+3*n+(6*n^3-23*n^2+19*n)*x+(12*n^3-48*n^2+46*n)*x^2+(8*n^3-36*n^2+44*n-8)*x^3)*P(n-1,x) + ((2*n^2-2*n)*x+(10*n^2-14*n)*x^2+(16*n^2-28*n+4)*x^3+(8*n^2-16*n+4)*x^4)*d/dx P(n-1,x) for n >= 2, with P(0,x) = 0, P(1,x) = 1.
%t MathematicaP[0, x_] := 0;
P[1, x_] := 1;
P[n_, x_] := P[n, x] = Expand[Together[(-(n^3 - 4*n^2 + 3*n + (6*n^3 - 23*n^2 + 19*n)*x + (12*n^3 - 48*n^2 + 46*n)*x^2 + (8*n^3 - 36*n^2 + 44*n - 8)*x^3)*P[n - 1, x] + ((2*n^2 - 2*n)*x + (10*n^2 - 14*n)*x^2 + (16*n^2 - 28*n + 4)*x^3 + (8*n^2 - 16*n + 4)*x^4)*D[P[n - 1, x], x])/(n^2 - n + (4*n^2 - 10*n + 6)*x + (4*n^2 - 12*n + 8)*x^2)]];
Table[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten%o PARI/GPP(N) = {my(v = vector(N + 1)); v[1] = 0; v[2] = 1; for(n = 2, N, my(i = n + 1); v[i] = (-(n^3 - 4*n^2 + 3*n + (6*n^3 - 23*n^2 + 19*n)*x + (12*n^3 - 48*n^2 + 46*n)*x^2 + (8*n^3 - 36*n^2 + 44*n - 8)*x^3)*v[i - 1] + ((2*n^2 - 2*n)*x + (10*n^2 - 14*n)*x^2 + (16*n^2 - 28*n + 4)*x^3 + (8*n^2 - 16*n + 4)*x^4)*deriv(v[i - 1], x))/(n^2 - n + (4*n^2 - 10*n + 6)*x + (4*n^2 - 12*n + 8)*x^2)); 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
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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-a139b2269602238f -
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-a139b2269602238f -
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-a139b2269602238f
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
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preserver_image derivative_polynomial, shift 0
e-a139b2269602238fLaguerre’s theorem on differential operators [SP14] polytool ?
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premise (sequence):
Triangle read by rows: triangle of repeated stepped binomial coefficients.
uses: Every row P_n, n >= 0, is zero or real-rooted with all roots in (-inf, 0]
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parent_provers periodic_product
e-35a33ce2a6b89415root: theorem checkParent-row provers of polytool polytool ?
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premise (sequence):
Triangle read by rows: triangle of repeated stepped binomial coefficients.
Related sequences ?
No candidate equalities or related sequences.
References
- [SP14] J Schur and G Polya. Über zwei Arten von Faktorenfolgen in der Theorie der algebraischen Gleichungen. J. Reine Angew. Math., 1914.