A136572 → (θ+1)²
palindromic γ-positive 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 | x7 | Pn(1) |
|---|---|---|---|---|---|---|---|---|---|
| 0 | 1 | 1 | |||||||
| 1 | 0 | 4 | 4 | ||||||
| 2 | 0 | 0 | 18 | 18 | |||||
| 3 | 0 | 0 | 0 | 96 | 96 | ||||
| 4 | 0 | 0 | 0 | 0 | 600 | 600 | |||
| 5 | 0 | 0 | 0 | 0 | 0 | 4320 | 4320 | ||
| 6 | 0 | 0 | 0 | 0 | 0 | 0 | 35280 | 35280 | |
| 7 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 322560 | 322560 |
Computed in your browser ?
Technical details
- Node id
n-d2e9afed41ff1350· revision 1 · JSON- Definition source
derived:theta_plus_one_squared- Fingerprint
f6-edf6954a4cd8adfc
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: yes
- γ-positive (gamma_positive): yes
- Nonnegative coefficients (
nonn): yes - Only rational roots (
rr_by_factors: every nonzero row is a product of linear factors over ℚ): yes
OEIS matches ?
- A052633: row sums, 13 terms agree OEIS nonn (row-sum match: finite agreement only) · view at the OEIS
- A001563: row sums, 15 terms agree OEIS nonn (row-sum match: finite agreement only) · view at the OEIS
- A094304: row sums, 15 terms agree OEIS nonn (row-sum match: finite agreement only) · view at the OEIS
- A094258: row sums, 15 terms agree OEIS nonn (row-sum match: finite agreement only) · view at the OEIS
- A052655: row sums, 13 terms agree OEIS nonn (row-sum match: finite agreement only) · view at the OEIS
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: 1; 1: 0, 4; 2: 0, 0, 18; 3: 0, 0, 0, 96; 4: 0, 0, 0, 0, 600; 5: 0, 0, 0, 0, 0, 4320; 6: 0, 0, 0, 0, 0, 0, 35280; 7: 0, 0, 0, 0, 0, 0, 0, 322560; 8: 0, 0, 0, 0, 0, 0, 0, 0, 3265920; 9: 0, 0, 0, 0, 0, 0, 0, 0, 0, 36288000;
%F FormulaThe row polynomials satisfy n*P(n,x) = (n^2+2*n+1)*x*P(n-1,x) for n >= 1, with P(0,x) = 1.
%t MathematicaP[0, x_] := 1;
P[n_, x_] := P[n, x] = Expand[Together[((n^2 + 2*n + 1)*x*P[n - 1, x])/(n)]];
Table[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten%o PARI/GPP(N) = {my(v = vector(N + 1)); v[1] = 1; for(n = 1, N, my(i = n + 1); v[i] = ((n^2 + 2*n + 1)*x*v[i - 1])/(n)); 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-76872140ee232c50 -
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-76872140ee232c50 -
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-76872140ee232c50
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 euler_polynomial, shift 0
e-76872140ee232c50Laguerre’s theorem on multiplier sequences [SP14; Bra15, Thm 40] polytool ?
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premise (sequence):
Triangle read by rows: row n consists of n zeros followed by n!.
uses: Every row P_n, n >= 0, is zero or real-rooted with all roots in (-inf, 0]
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parent_provers root_domain
e-8128a83cc2062067root: theorem checkParent-row provers of polytool polytool ?
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preserver_image mobius, shift 0
e-7d7235cf57d80f69Affine, reversal and Möbius substitutions (elementary) polytool ?
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premise (sequence):
Triangle read by rows: row n consists of n zeros followed by n!.
uses: Every row P_n, n >= 0, is zero or real-rooted with all roots in (-inf, 0]
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premise (sequence):
Triangle read by rows: row n consists of n zeros followed by n!.
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-
premise (sequence):
Triangle read by rows: row n consists of n zeros followed by n!.
Related sequences ?
Same fingerprint (75)
Equal up to content, sign, reversal and a small index shift.
- A010054 → reverse → θ+1
- A135838 → γ
- A010054 → reverse → θ+1
- A010054 → reverse → D
- A010054 → reverse → θ+1
- A136572 → θ+1
- basis-map coefficients of Irregular triangle read by rows formed by taking every other row of the Delannoy array (A0082…
- basis-map coefficients of A021012 → θ+1
- A085881 → γ
- A127733: Triangle read by rows: n-th row is n^2 preceded by (n-1) zeros.
- basis-map coefficients of A112227 → (θ+1)²
- basis-map coefficients of Square array of binomial coefficients T(n,k) = binomial(n,k), n >= 0, k >= 0, read by downwar…
- A023531 → (θ+1)² → reverse
- basis-map coefficients of A030528, shifted → (θ+1)²
- A356546 → γ
- A010054 → reverse → D
- basis-map coefficients of A026729, shifted → (θ+1)²
- A038325 → γ
- A127648: Triangle read by rows: row n consists of n zeros followed by n+1.
- A178821 → γ
- basis-map coefficients of A112227 → θ+1
- basis-map coefficients of A112227 → D
- A136572: Triangle read by rows: row n consists of n zeros followed by n!.
- basis-map coefficients of A026729 → (θ+1)²
- A133080 → Veronese 2
- A178822 → γ
- basis-map coefficients of Triangle of coefficients in expansion of x^n in terms of Laguerre polynomials L_n(x).
- A038221 → γ
- basis-map coefficients of A297191, shifted → θ+1
- basis-map coefficients of A297191, shifted → (θ+1)²
- A010054 → reverse → (θ+1)²
- basis-map coefficients of A021012 → reverse
- basis-map coefficients of A030528, shifted → θ+1
- A010054 → reverse → (θ+1)²
- A023531 → (θ+1)² → (θ+1)²
- A344565 → γ
- A023531 → θ+1
- A023531 → (θ+1)² → θ+1
- A010054 → reverse → reverse
- basis-map coefficients of A026729, shifted → D
- basis-map coefficients of A021012 → D
- A127773: Triangle read by rows: row n consists of n-1 zeros followed by n(n+1)/2.
- A130123 → reverse
- A007318 → D → γ
- A010054: a(n) = 1 if n is a triangular number, otherwise 0.
- A010054 → reverse → D
- A023531: a(n) = 1 if n is of the form m(m+3)/2, otherwise 0.
- A131431: 3n + 1 preceded by n zeros.
- A130123 → D
- basis-map coefficients of A021012 → (θ+1)²
- A196347 → γ
- A130123: Infinite lower triangular matrix with 2^k in the right diagonal and the rest zeros. Triangle, T(n,k), n zeros …
- basis-map coefficients of A297191, shifted → D
- A136572 → D
- A023531 → D → (θ+1)²
- A028326 → γ
- basis-map coefficients of A026729, shifted → reverse
- A132440: Infinitesimal Pascal matrix: generator (lower triangular matrix representation) of the Pascal matrix, the clas…
- A023531 → (θ+1)² → D
- A130123 → θ+1
- basis-map coefficients of Triangle read by rows: T(n,k) = binomial(k,n-k). shifted by x -> -x + 0
- A023531 → 2D+1+2n → Veronese 2 (j=1)
- A178820 → γ
- basis-map coefficients of A026729 → D
- A130123 → (θ+1)²
- basis-map coefficients of A026729, shifted → θ+1
- basis-map coefficients of A030528, shifted → D
- A023531 → 2D+1+2n → Veronese 2
- A010054 → reverse → reverse
- A198954: Expansion of the rotational partition function for a heteronuclear diatomic molecule.
- A156992 → γ
- basis-map coefficients of A scaled Hermite triangle.
- A038338 → γ
- basis-map coefficients of Square array of binomial coefficients T(n,k) = binomial(n,k), n >= 0, k >= 0, read by downwar…
- basis-map coefficients of A030528, shifted → reverse
References
- [Bra15] Petter Brändén. Unimodality, log-concavity, real-rootedness and beyond. Handbook of enumerative combinatorics, :437–483, March 2015. doi:10.1201/b18255-10
- [SP14] J Schur and G Polya. Über zwei Arten von Faktorenfolgen in der Theorie der algebraischen Gleichungen. J. Reine Angew. Math., 1914.