A008278 → x ↦ x+1 (shift +1) → x ↦ x+1
nonnegative coefficients
Proved for all n: all roots real, in (−∞, −1] · 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 | 3 | 1 | 4 | ||||||
| 2 | 11 | 7 | 1 | 19 | |||||
| 3 | 49 | 46 | 13 | 1 | 109 | ||||
| 4 | 257 | 322 | 139 | 23 | 1 | 742 | |||
| 5 | 1539 | 2427 | 1429 | 378 | 41 | 1 | 5815 | ||
| 6 | 10299 | 19645 | 14744 | 5438 | 991 | 75 | 1 | 51193 | |
| 7 | 75905 | 170236 | 155822 | 74178 | 19261 | 2574 | 141 | 1 | 498118 |
Computed in your browser ?
Technical details
- Node id
n-1639e69c5d7e0691· revision 1 · JSON- Definition source
derived:shift_x_plus_one- Fingerprint
f6-75d63132b26da3ac
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: 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 ?
- A004212: row sums, 15 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: 3, 1; 2: 11, 7, 1; 3: 49, 46, 13, 1; 4: 257, 322, 139, 23, 1; 5: 1539, 2427, 1429, 378, 41, 1; 6: 10299, 19645, 14744, 5438, 991, 75, 1; 7: 75905, 170236, 155822, 74178, 19261, 2574, 141, 1; 8: 609441, 1573732, 1703914, 997646, 338671, 65938, 6707, 271, 1; 9: 5284451, 15459637, 19361158, 13492184, 5683129, 1466449, 222629, 17650, 529, 1;
%F FormulaThe row polynomials satisfy P(n,x) = (2*n+1+n*x)*P(n-1,x) - (4+4*x+x^2)*d/dx P(n-1,x) for n >= 1, with P(0,x) = 1.
%t MathematicaP[0, x_] := 1;
P[n_, x_] := P[n, x] = Expand[(2*n + 1 + n*x)*P[n - 1, x] - (4 + 4*x + x^2)*D[P[n - 1, x], x]];
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] = (2*n + 1 + n*x)*v[i - 1] - (4 + 4*x + x^2)*deriv(v[i - 1], x)); 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, -1]
Every polynomial of the sequence has only real roots, inside the stated interval.by the cited steps:
e-8abcc7766de04335 -
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-8abcc7766de04335 -
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-8abcc7766de04335
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 affine, shift 0
e-8abcc7766de04335Affine, reversal and Möbius substitutions (elementary) polytool ?
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premise (sequence):
Triangle T(n,k) of numbers with e.g.f. exp((exp((1+x)*y)-1)/(1+x)), k=0..n-1.
uses: Every row P_n, n >= 0, is zero or real-rooted with all roots in (-inf, 0]
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preserver_image affine, shift 1
e-236d0fb15dc6eca0Affine, reversal and Möbius substitutions (elementary) polytool ?
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premise (sequence):
Reflected triangle of Stirling numbers of 2nd kind, S(n,n-k+1), n >= 1, 1 <= k <= n.
uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 0]
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theorem_check liu_wang
e-8e580efc86a38a12root: theorem checkLiu–Wang theorem [LW07, Thm 2.1, Cor 2.4] ?
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preserver_image reversal, shift 0
e-3256729839b26765Affine, reversal and Möbius substitutions (elementary) polytool ?
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premise (sequence):
Triangle of Stirling numbers of the second kind, S2(n,k), n >= 1, 1 <= k <= n.
uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 0]
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theorem_check liu_wang
e-995393ce4e49a8d6root: theorem checkLiu–Wang theorem [LW07, Thm 2.1, Cor 2.4] ?
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basis_map A008277
e-c52960bc5e97caa0Ray basis map theorem [MW08, Thm 2] polytool RealRooted rayBasisMap_maps_realRootedIn_iff ?
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premise (sequence):
basis-map coefficients of Square array of binomial coefficients T(n,k) = binomial(n,k), n >= 0, k >= 0, read by downwar…
uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 0]
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parent_provers periodic_product
e-6e85c0971e84e272root: theorem checkParent-row provers of polytool polytool ?
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preserver_image mobius, shift 0
e-ad67990681a86223Affine, reversal and Möbius substitutions (elementary) polytool ?
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premise (sequence):
basis-map coefficients of Square array of binomial coefficients T(n,k) = binomial(n,k), n >= 0, k >= 0, read by downwar…
uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 0]
-
premise (sequence):
basis-map coefficients of Square array of binomial coefficients T(n,k) = binomial(n,k), n >= 0, k >= 0, read by downwar…
-
-
premise (sequence):
basis-map coefficients of Square array of binomial coefficients T(n,k) = binomial(n,k), n >= 0, k >= 0, read by downwar…
-
preserver_image reversal, shift 0
e-d527982dc7c0aa3bAffine, reversal and Möbius substitutions (elementary) polytool ?
-
premise (sequence):
Reflected triangle of Stirling numbers of 2nd kind, S(n,n-k+1), n >= 1, 1 <= k <= n.
uses: Every row P_n, n >= 1, is zero or real-rooted with all roots in (-inf, 0]
-
premise (sequence):
Reflected triangle of Stirling numbers of 2nd kind, S(n,n-k+1), n >= 1, 1 <= k <= n.
-
-
premise (sequence):
Triangle of Stirling numbers of the second kind, S2(n,k), n >= 1, 1 <= k <= n.
-
-
premise (sequence):
Reflected triangle of Stirling numbers of 2nd kind, S(n,n-k+1), n >= 1, 1 <= k <= n.
-
-
premise (sequence):
Triangle T(n,k) of numbers with e.g.f. exp((exp((1+x)*y)-1)/(1+x)), k=0..n-1.
Related sequences ?
No candidate equalities or related sequences.
References
- [LW07] Lily L. Liu and Yi Wang. A unified approach to polynomial sequences with only real zeros. Advances in Applied Mathematics, 38(4):542–560, May 2007. doi:10.1016/j.aam.2006.02.003
- [MW08] Shi-Mei Ma and Yi Wang. q-Eulerian polynomials and polynomials with only real zeros. The Electronic Journal of Combinatorics, 15(1):Research Paper 17, January 2008. doi:10.37236/741