A272866 → basis A013609

nonnegative coefficients

Proved for all n: all roots real, in (−∞, 0] · coefficients of one sign · Hadamard kernel what this means

Recurrence
\(P_{n}(x) = \left(5 + 10\,x + 4\,x^{2}\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
011
1510419
2251001408016361
3125750180022001440480646859
4625500017000320003640025600108802560256130321
5312531250137500350000570000620000456000224000704001280010242476099
615625187500101250032500006900000102000001076000081600004416000166400041472061440409647045881
778125109375070000002712500071050000133000000183400000189200000146720000851200003637760011110400229376028672016384893871739

Generated b-files: A001029 (row sums) ?

Computed in your browser ?

Technical details
Node id
n-feae95e8ddee939b · revision 1 · JSON
Definition source
derived:basis_map_A013609
Fingerprint
f6-c64e29f1cee5cd50

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): no

OEIS matches ?

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 Example
Triangle begins:
  0:       1;
  1:       5,       10,         4;
  2:      25,      100,       140,         80,         16;
  3:     125,      750,      1800,       2200,       1440,         480,          64;
  4:     625,     5000,     17000,      32000,      36400,       25600,       10880,        2560,         256;
  5:    3125,    31250,    137500,     350000,     570000,      620000,      456000,      224000,       70400,       12800,        1024;
  6:   15625,   187500,   1012500,    3250000,    6900000,    10200000,    10760000,     8160000,     4416000,     1664000,      414720,       61440,        4096;
  7:   78125,  1093750,   7000000,   27125000,   71050000,   133000000,   183400000,   189200000,   146720000,    85120000,    36377600,    11110400,     2293760,     286720,      16384;
  8:  390625,  6250000,  46250000,  210000000,  654500000,  1484000000,  2531200000,  3312000000,  3359200000,  2649600000,  1619968000,   759808000,   268083200,   68812800,   12124160,   1310720,    65536;
  9: 1953125, 35156250, 295312500, 1537500000, 5557500000, 14805000000, 30114000000, 47808000000, 60040800000, 60088000000, 48032640000, 30597120000, 15418368000, 6064128000, 1821081600, 403046400, 61931520, 5898240, 262144;
%F Formula
The row polynomials satisfy P(n,x) = (5+10*x+4*x^2)*P(n-1,x) for n >= 1, with P(0,x) = 1.
%t Mathematica
P[0, x_] := 1;
P[n_, x_] := P[n, x] = Expand[(5 + 10*x + 4*x^2)*P[n - 1, x]];
Table[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten
%o PARI/GP
P(N) = {my(v = vector(N + 1)); v[1] = 1; for(n = 1, N, my(i = n + 1); v[i] = (5 + 10*x + 4*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-89275777750acd05
  • 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-89275777750acd05
  • 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-89275777750acd05

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

No candidate equalities or related sequences.