basis-map coefficients of A112227 → θ+1 → basis A013611
nonnegative coefficientsonly rational roots
Proved for all n all roots real, in (−∞, 0]coefficients of one signHadamard kernelinterlacing (weak)
Recurrence
\(\left(1 + n\right)\,P_{n}(x) = \left(2 + 8\,x + n + 4\,n x\right)\,P_{n-1}(x)\)
\(P_{1}(x) = 3 + 24\,x + 48\,x^{2}\)
Rows ?
| n | x0 | x1 | x2 | x3 | x4 | x5 | x6 | x7 | x8 | x9 | Pn(1) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 3 | 24 | 48 | 75 | |||||||
| 2 | 4 | 48 | 192 | 256 | 500 | ||||||
| 3 | 5 | 80 | 480 | 1280 | 1280 | 3125 | |||||
| 4 | 6 | 120 | 960 | 3840 | 7680 | 6144 | 18750 | ||||
| 5 | 7 | 168 | 1680 | 8960 | 26880 | 43008 | 28672 | 109375 | |||
| 6 | 8 | 224 | 2688 | 17920 | 71680 | 172032 | 229376 | 131072 | 625000 | ||
| 7 | 9 | 288 | 4032 | 32256 | 161280 | 516096 | 1032192 | 1179648 | 589824 | 3515625 | |
| 8 | 10 | 360 | 5760 | 53760 | 322560 | 1290240 | 3440640 | 5898240 | 5898240 | 2621440 | 19531250 |
Compute more
?
Technical details
- Node id
n-43d60147a8c06e7d· revision 0 · JSON- Definition source
derived:basis_map_A013611- Fingerprint
f6-03d7b8417365c509
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 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: 3, 24, 48; 2: 4, 48, 192, 256; 3: 5, 80, 480, 1280, 1280; 4: 6, 120, 960, 3840, 7680, 6144; 5: 7, 168, 1680, 8960, 26880, 43008, 28672; 6: 8, 224, 2688, 17920, 71680, 172032, 229376, 131072; 7: 9, 288, 4032, 32256, 161280, 516096, 1032192, 1179648, 589824; 8: 10, 360, 5760, 53760, 322560, 1290240, 3440640, 5898240, 5898240, 2621440; 9: 11, 440, 7920, 84480, 591360, 2838528, 9461760, 21626880, 32440320, 28835840, 11534336; 10: 12, 528, 10560, 126720, 1013760, 5677056, 22708224, 64880640, 129761280, 173015040, 138412032, 50331648;
%F FormulaThe row polynomials satisfy (n+1)*P(n,x) = (n+2+(4*n+8)*x)*P(n-1,x) for n >= 2, with P(1,x) = 3 + 24*x + 48*x^2.
%t MathematicaP[1, x_] := 3 + 24*x + 48*x^2;
P[n_, x_] := P[n, x] = Expand[Together[((n + 2 + (4*n + 8)*x)*P[n - 1, x])/(n + 1)]];
Table[CoefficientList[P[n, x], x], {n, 1, 10}] // Flatten%o PARI/GPP(N) = {my(v = vector(N)); v[1] = 3 + 24*x + 48*x^2; for(n = 2, N, my(i = n); v[i] = ((n + 2 + (4*n + 8)*x)*v[i - 1])/(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)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 Geometric basis map (elementary)
-
Hadamard kernel (Malo)?
Rows P_n, n ≥ 1, are Hadamard kernels (preserve real-rootedness)
derived from Geometric basis map (elementary)
- Interlacing of consecutive rows? Rows P_(m-1), P_m interlace (weak, unordered) for every m ≥ 2
Proof chains ? JSON
-
Geometric basis map (elementary) polytool ? step ›
Related ?
Same fingerprint ?
- basis-map coefficients of A026729, shifted → D → basis A013611
- basis-map coefficients of A030528, shifted → basis A013611
- A132440 → θ+1 → basis A013611
- A038330 → basis A007318
- image under θ+1 → basis A013611
- image under θ+1 → θ+1 → D → basis A013611
- A038330 → basis A007318 → D
- A136572 → θ+1 → basis A013611
- A136572 → basis A013611 → reverse
- basis-map coefficients of A112227 → (θ+1)² → basis A013611
- basis-map coefficients of A026729, shifted → basis A013611
- A136572 → D → basis A013611
- A130123 → basis A013611
- A131431 → D → basis A013611
- A120910 → basis A007318 → basis A007318
- A131431 → θ+1 → basis A013611
- basis-map coefficients of A112227 → basis A013611 → reverse
- A038330 → basis A007318 → reverse
- A130123 → (θ+1)² → basis A013611
- A132440 → basis A013611
- A027466 → basis A013609 → D
- basis-map coefficients of A026729 → D → basis A013611
- basis-map coefficients of A030528, shifted → (θ+1)² → basis A013611
- A013611: Triangle of coefficients in expansion of (1+4x)^n.
- A136572 → basis A013611
- basis-map coefficients of A026729 → basis A013611 → D
- A013610 → basis A013611 → x ↦ x/(x+1)
- A130123 → basis A013611 → D
- A013611 → D
- A027467 → basis A013611 → D
- A038231 → D
- A130123 → D → basis A013611
- A027466 → basis A013609
- image under θ+1 → (θ+1)² → basis A013611
- basis-map coefficients of A026729 → basis A013611 → reverse
- A136572 → basis A013611 → D
- A134309 → basis A013611
- basis-map coefficients of A021012 → θ+1 → basis A013611
- A131436 → basis A013611
- basis-map coefficients of A021012 → basis A013611
- A129186 → basis A013611
- A027467 → basis A013611
- A136572 → (θ+1)² → basis A013611
- A136521 → basis A013611
- A027467 → basis A013611 → reverse
- A013611 → D → D
- basis-map coefficients of A112227 → basis A013611 → D
- basis-map coefficients of A112227 → basis A013611
- basis-map coefficients of A026729 → (θ+1)² → basis A013611
- A038329 → D
- basis-map coefficients of A026729, shifted → (θ+1)² → basis A013611
- basis-map coefficients of A026729, shifted → θ+1 → basis A013611
- A038231: Triangle whose (i,j)-th entry is binomial(i,j)*4^(i-j).
- basis-map coefficients of A030528, shifted → θ+1 → basis A013611
- A130123 → θ+1 → basis A013611
- Triangle whose (i,j)-th entry is binomial(i,j)*12^(i-j)*3^j.
- A038231 → D → D
- A038303 → basis A007318 → basis A013610
- basis-map coefficients of A030528, shifted → D → basis A013611
- basis-map coefficients of A026729 → basis A013611
- A127648 → D → basis A013611
- A131431 → basis A013611
- A038329 → reverse
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.