A200536 → basis A007318
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 | x8 | x9 | x10 | x11 | x12 | x13 | x14 | Pn(1) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 0 | 1 | 1 | ||||||||||||||
| 1 | 6 | 7 | 2 | 15 | ||||||||||||
| 2 | 36 | 84 | 73 | 28 | 4 | 225 | ||||||||||
| 3 | 216 | 756 | 1098 | 847 | 366 | 84 | 8 | 3375 | ||||||||
| 4 | 1296 | 6048 | 12312 | 14280 | 10321 | 4760 | 1368 | 224 | 16 | 50625 | ||||||
| 5 | 7776 | 45360 | 118800 | 183960 | 186510 | 129367 | 62170 | 20440 | 4400 | 560 | 32 | 759375 | ||||
| 6 | 46656 | 326592 | 1045872 | 2026080 | 2644380 | 2449692 | 1651609 | 816564 | 293820 | 75040 | 12912 | 1344 | 64 | 11390625 | ||
| 7 | 279936 | 2286144 | 8654688 | 20130768 | 32140584 | 37260972 | 32346258 | 21360031 | 10782086 | 4140108 | 1190392 | 248528 | 35616 | 3136 | 128 | 170859375 |
Generated b-files: A001024 (row sums) ?
Computed in your browser ?
Technical details
- Node id
n-a19ad5e2037d7c6a· revision 1 · JSON- Definition source
derived:basis_map_A007318- Fingerprint
f6-10e88990a58171dc
Observed on the stored rows ?
- Degrees: 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28 (affine: slope 2, 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): yes
OEIS matches ?
- A001024: row sums, 15 terms agree OEIS nonn (row-sum match: finite agreement only) · view at the OEIS · generated b-file 200 terms from n = 0 ?
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: 1; 1: 6, 7, 2; 2: 36, 84, 73, 28, 4; 3: 216, 756, 1098, 847, 366, 84, 8; 4: 1296, 6048, 12312, 14280, 10321, 4760, 1368, 224, 16; 5: 7776, 45360, 118800, 183960, 186510, 129367, 62170, 20440, 4400, 560, 32; 6: 46656, 326592, 1045872, 2026080, 2644380, 2449692, 1651609, 816564, 293820, 75040, 12912, 1344, 64; 7: 279936, 2286144, 8654688, 20130768, 32140584, 37260972, 32346258, 21360031, 10782086, 4140108, 1190392, 248528, 35616, 3136, 128; 8: 1679616, 15676416, 68491008, 185939712, 351068256, 488811456, 519185520, 429105936, 278905249, 143035312, 57687280, 18104128, 4334176, 765184, 93952, 7168, 256; 9: 10077696, 105815808, 524040192, 1626428160, 3544969536, 5762225952, 7238929824, 7186557168, 5715544086, 3668760487, 1905181362, 798506352, 268108512, 71138592, 14588352, 2231040, 239616, 16128, 512;
%F FormulaThe row polynomials satisfy P(n,x) = (6+7*x+2*x^2)*P(n-1,x) for n >= 1, with P(0,x) = 1.
%t MathematicaP[0, x_] := 1;
P[n_, x_] := P[n, x] = Expand[(6 + 7*x + 2*x^2)*P[n - 1, 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] = (6 + 7*x + 2*x^2)*v[i - 1]); 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-6e97878f95ac8f6d -
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-6e97878f95ac8f6d -
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-6e97878f95ac8f6d
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
-
basis_map A007318
e-6e97878f95ac8f6dGeometric basis map (elementary) polytool ?
-
premise (sequence):
Triangle, read by rows of 2*n+1 terms, where row n lists the coefficients in (1+3*x+2*x^2)^n.
uses: Every row P_n, n >= 0, is zero or real-rooted with all roots in (-inf, 0]
-
parent_provers periodic_product
e-982ad459e6d62a8eroot: theorem checkParent-row provers of polytool polytool ?
-
-
premise (sequence):
Triangle, read by rows of 2*n+1 terms, where row n lists the coefficients in (1+3*x+2*x^2)^n.
Related sequences ?
Same fingerprint (1)
Equal up to content, sign, reversal and a small index shift.