basis-map coefficients of A026729 → basis A007318 → θ+1
nonnegative coefficientsonly rational roots
Proved for all n all roots real, in (−∞, 0]coefficients of one signHadamard kernelinterlacing (weak)
Recurrence
\(\left(1 - x + n x\right)\,P_{n}(x) = \left(1 + x + n x + n x^{2}\right)\,P_{n-1}(x)\)
\(P_{1}(x) = 1\)
Rows ?
| n | x0 | x1 | x2 | x3 | x4 | x5 | x6 | x7 | Pn(1) |
|---|---|---|---|---|---|---|---|---|---|
| 1 | 1 | 1 | |||||||
| 2 | 1 | 2 | 3 | ||||||
| 3 | 1 | 4 | 3 | 8 | |||||
| 4 | 1 | 6 | 9 | 4 | 20 | ||||
| 5 | 1 | 8 | 18 | 16 | 5 | 48 | |||
| 6 | 1 | 10 | 30 | 40 | 25 | 6 | 112 | ||
| 7 | 1 | 12 | 45 | 80 | 75 | 36 | 7 | 256 | |
| 8 | 1 | 14 | 63 | 140 | 175 | 126 | 49 | 8 | 576 |
Compute more
?
Technical details
- Node id
n-00f17f8389bd6548· revision 0 · JSON- Definition source
derived:theta_plus_one- Fingerprint
f6-e99c3824c4864868
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): yes
Matches ?
No OEIS matches.
Submission text ?
Atlas rows n = 1, …, ascending powers of x
%e ExampleTriangle begins: 1: 1; 2: 1, 2; 3: 1, 4, 3; 4: 1, 6, 9, 4; 5: 1, 8, 18, 16, 5; 6: 1, 10, 30, 40, 25, 6; 7: 1, 12, 45, 80, 75, 36, 7; 8: 1, 14, 63, 140, 175, 126, 49, 8; 9: 1, 16, 84, 224, 350, 336, 196, 64, 9; 10: 1, 18, 108, 336, 630, 756, 588, 288, 81, 10;
%F FormulaThe row polynomials satisfy (1+(n-1)*x)*P(n,x) = (1+(n+1)*x+n*x^2)*P(n-1,x) for n >= 2, with P(1,x) = 1.
%t MathematicaP[1, x_] := 1;
P[n_, x_] := P[n, x] = Expand[Together[((1 + (n + 1)*x + n*x^2)*P[n - 1, x])/(1 + (n - 1)*x)]];
Table[CoefficientList[P[n, x], x], {n, 1, 10}] // Flatten%o PARI/GPP(N) = {my(v = vector(N)); v[1] = 1; for(n = 2, N, my(i = n); v[i] = ((1 + (n + 1)*x + n*x^2)*v[i - 1])/(1 + (n - 1)*x)); 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)polytool c48629374597
Properties
- Real-rooted? Every row P_n, n ≥ 1, is zero or real-rooted with all roots in (−∞, 0]
-
Coefficients of one sign?
Every nonzero row, n ≥ 1: the coefficients of P_n have one sign
derived from Laguerre’s theorem on multiplier sequences
-
Hadamard kernel (Malo)?
Rows P_n, n ≥ 1, are Hadamard kernels (preserve real-rootedness)
derived from Laguerre’s theorem on multiplier sequences
- Interlacing of consecutive rows? Rows P_(m-1), P_m interlace (weak, unordered) for every m ≥ 2
Proof chains ? JSON
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Laguerre’s theorem on multiplier sequences [SP14; Bra15, Thm 7.1 of arXiv:1410.6601] polytool ? step ›
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from
shift_x_plus_one of basis-map coefficients of Square array of binomial coefficients T(n,k) = binomial(n,k), n >= 0, k >…?
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Affine, reversal and Möbius substitutions (elementary) polytool ? step ›
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Affine, reversal and Möbius substitutions (elementary) polytool ? step ›
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from
shift_x_plus_one of basis-map coefficients of Square array of binomial coefficients T(n,k) = binomial(n,k), n >= 0, k >…?
- ↑ Affine, reversal and Möbius substitutions (elementary) (above)
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Affine, reversal and Möbius substitutions (elementary) polytool ? step ›
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from
veronese parent of Triangle T(n,k) with diagonals T(n,n-k) = binomial(n,3k).?
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Row-hypergeometric rows (multiplier sequences) [SP14; Bra15, Thm 7.1 of arXiv:1410.6601] polytool RealRooted RealRooted.isPFMultiplierSequence_eval_of_roots_nonpos RealRooted RealRooted.isPFMultiplierSequence_inv_ascPochhammer RealRooted RealRooted.IsPFMultiplierSequence.mul ? step › direct check
-
from
veronese parent of Triangle T(n,k) with diagonals T(n,n-k) = binomial(n,3k).?
-
Affine, reversal and Möbius substitutions (elementary) polytool ? step ›
-
from
veronese parent of Triangle T(n,k) with diagonals T(n,n-k) = binomial(n,3k).?
-
Row-hypergeometric rows (multiplier sequences) [SP14; Bra15, Thm 7.1 of arXiv:1410.6601] polytool RealRooted RealRooted.isPFMultiplierSequence_eval_of_roots_nonpos RealRooted RealRooted.isPFMultiplierSequence_inv_ascPochhammer RealRooted RealRooted.IsPFMultiplierSequence.mul ? step › direct check
-
from
veronese parent of Triangle T(n,k) with diagonals T(n,n-k) = binomial(n,3k).?
-
Affine, reversal and Möbius substitutions (elementary) polytool ? step ›
-
from
veronese parent of Triangle T(n,k) with diagonals T(n,n-k) = binomial(n,3k).?
-
Row-hypergeometric rows (multiplier sequences) [SP14; Bra15, Thm 7.1 of arXiv:1410.6601] polytool RealRooted RealRooted.isPFMultiplierSequence_eval_of_roots_nonpos RealRooted RealRooted.isPFMultiplierSequence_inv_ascPochhammer RealRooted RealRooted.IsPFMultiplierSequence.mul ? step › direct check
-
from
veronese parent of Triangle T(n,k) with diagonals T(n,n-k) = binomial(n,3k).?
-
from
shift_x_plus_one of basis-map coefficients of Square array of binomial coefficients T(n,k) = binomial(n,k), n >= 0, k >…?
- ↑ Geometric basis map (elementary) (above)
- ↑ Affine, reversal and Möbius substitutions (elementary) (above)
- ↑ Affine, reversal and Möbius substitutions (elementary) (above)
- ↑ Affine, reversal and Möbius substitutions (elementary) (above)
-
-
from
shift_x_plus_one of basis-map coefficients of Square array of binomial coefficients T(n,k) = binomial(n,k), n >= 0, k >…?
Related ?
Same fingerprint ?
- A038221 → D+1
- A135838 → D+1
- basis-map coefficients of A113214, shifted → basis A013609 → θ+1
- A028326 → D → D+1
- A028326 → D+1
- A178822 → basis A013609 → D+1
- A038208 → D → D+1
- A085881 → D+1
- basis-map coefficients of A113214, shifted → θ+1
- A027465 → basis A013611 → θ+1
- A038325 → D+1
- A094305 → θ+1
- A120910 → basis A013610 → θ+1
- basis-map coefficients of A113214, shifted → D → θ+1
- A028326 → D → θ+1
- A124860 → D+1
- basis-map coefficients of A026729 → basis A007318 → D+1
- basis-map coefficients of A113214, shifted → D+1
- A094305 → D+1
- A038325 → basis A013609 → θ+1
- A085880 → D → D+1
- A085880 → basis A013609 → θ+1
- basis-map coefficients of A113214, shifted → basis A013609 → D+1
- A038325 → basis A013609 → D+1
- A178821 → basis A013609 → θ+1
- basis-map coefficients of A127647 → θ+1
- A038338 → D+1
- A038221 → basis A013609 → D+1
- A124860 → θ+1
- A038208 → θ+1
- basis-map coefficients of A026729, shifted → basis A007318 → D+1
- A131431 → x ↦ x+1 → D+1
- A007318 → ×(−(1/2)n+(1/2)n²) → D+1
- A093375 → D
- A085881 → θ+1
- A196347 → basis A013609 → θ+1
- A356546 → basis A013609 → D+1
- A196347 → θ+1
- A085880 → D → θ+1
- A178821 → D+1
- basis-map coefficients of A127647 → D+1
- A003506 → D → θ+1
- basis-map coefficients of A112227 → x ↦ x+1 → D+1
- A178821 → θ+1
- A085880 → θ+1
- A120910 → basis A013610 → D+1
- A038338 → basis A013609 → D+1
- A156992 → D+1
- A028326 → basis A013609 → D+1
- A085880 → D+1
- A007318 → ×(−(1/2)n+(1/2)n²) → θ+1
- A038208 → D+1
- A038330 → basis A013611 → D+1
- A156992 → basis A013609 → θ+1
- A085880 → basis A013609 → D+1
- A085881 → basis A013609 → θ+1
- A216973 → θ+1
- A178820 → basis A013609 → D+1
- A156992 → θ+1
- A093375: Array T(m,n) read by ascending antidiagonals: T(m,n) = m*binomial(n+m-2, n-1) for m, n >= 1.
- basis-map coefficients of A112227 → x ↦ x+1 → θ+1
- A134346 → D+1
- A103406: Triangle read by rows: n-th row = unsigned coefficients of the characteristic polynomials of an n X n matrix w…
- A376827 → θ+1
- A344565 → D+1
- A178820 → D+1
- A085881 → basis A013609 → D+1
- A178822 → basis A013609 → θ+1
- A038208 → D → θ+1
- A135065 → D+1
- A135838 → θ+1
- A134346 → θ+1
- A028326 → θ+1
- A038221 → θ+1
- A376827 → D+1
- A178821 → basis A013609 → D+1
- A178820 → basis A013609 → θ+1
- A028326 → basis A013609 → θ+1
- A196347 → basis A013609 → D+1
- A093375 → D → D
- basis-map coefficients of A113214, shifted → D → D+1
- A178822 → D+1
- basis-map coefficients of A026729, shifted → basis A007318 → θ+1
- A027465 → basis A013611 → D+1
- A356546 → θ+1
- A356546 → D+1
- A178820 → θ+1
- A344565 → θ+1
- A178822 → θ+1
- A156992 → basis A013609 → D+1
- A038338 → basis A013609 → θ+1
- A038221 → basis A013609 → θ+1
- A038330 → basis A013611 → θ+1
- A135065 → θ+1
- A131431 → x ↦ x+1 → θ+1
- A038338 → θ+1
- A131431 → D+1 → basis A007318
- A038325 → θ+1
- A196347 → D+1
- A356546 → basis A013609 → θ+1
References
- [Bra06] Petter Brändén. On linear transformations preserving the Pólya frequency property. Transactions of the American Mathematical Society, 358(8):3697–3716, February 2006. doi:10.1090/s0002-9947-06-03856-6
- [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.