basis-map coefficients of A297191, shifted → basis A013610

nonnegative coefficients only rational roots

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

Recurrence
\(P_{n}(x) = \left(1 + 6\,x + 9\,x^{2}\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14x15x16x17x18x19x20x21x22x23x24x25x26x27x28Pn(1)
011
116916
21125410881256
3118135540121514587294096
412425215125670136082041217496656165536
513040532401701061236153090262440295245196830590491048576
61365945940400951924566735961732104324769543302603897234212576453144116777216
7142819982881081486486218918775057841970268339405366591080496448150848361131223205224782969268435456
8148108015120147420106142458378322501928084440070225173520472864392773778096967222620892820880573956280229582512430467214294967296
9154137722032247860208202413533156695990882870962389569874602583866142563752612898656707241366015946414635885140117087081126586148313232452293438742048968719476736
101601710307803924453767472282560401695362408264891703305956680109096570442975361012066945622770123591918960185387878440222465454128208561363245147219785820736098929102324522934034867844011099511627776
1116620794158059251563991625439287737297972820980109709790717860381837996541249651625043436541968867930481466601529449997130244711999540832118449939733400777052442283398087703517898826591808054471966312301277704663138105960917592186044416
1217224845464886070610328472981204847569294484825425231257356012321158102055444421844211681437099368796397965979051293806266490641876125329812831659614940591446959269749525214524813744449400761393368370505710450262117175488287286611724520842259436291848282429536481281474976710656
1317829257020012109501598454016783767014386086001025008627561500517650313652640015136866606552051324977457001658191579380046192479711300110861951307120228652774570935403504896301650605257344452475764535592992600802762372642230688082033693340469146841154550244772264950200917895993563252202950384551825418658283294503599627370496
141843402884521658475238820402746434602589495480203922769051359485127007749065223903804086564460161673678989555969489685768019187645418540053725407171912013095567998153552773179105491340508416169340079080276237264223001083729203067010512385476606480120118225003970946609252391615117560578274475944847527757174845352689608252831083622135167295796362287679245496172057594037927936

Generated b-files: A001025 (row sums) ?

Computed in your browser ?

Technical details
Node id
n-eb3f8d5fd252d0c9 · revision 1 · JSON
Definition source
derived:basis_map_A013610
Fingerprint
f6-12929af9fbcc0757

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 ?

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: 1,  6,    9;
  2: 1, 12,   54,   108,     81;
  3: 1, 18,  135,   540,   1215,    1458,      729;
  4: 1, 24,  252,  1512,   5670,   13608,    20412,    17496,      6561;
  5: 1, 30,  405,  3240,  17010,   61236,   153090,   262440,    295245,    196830,      59049;
  6: 1, 36,  594,  5940,  40095,  192456,   673596,  1732104,   3247695,   4330260,    3897234,    2125764,     531441;
  7: 1, 42,  819,  9828,  81081,  486486,  2189187,  7505784,  19702683,  39405366,   59108049,   64481508,   48361131,    22320522,     4782969;
  8: 1, 48, 1080, 15120, 147420, 1061424,  5837832, 25019280,  84440070, 225173520,  472864392,  773778096,  967222620,   892820880,   573956280,   229582512,   43046721;
  9: 1, 54, 1377, 22032, 247860, 2082024, 13533156, 69599088, 287096238, 956987460, 2583866142, 5637526128, 9865670724, 13660159464, 14635885140, 11708708112, 6586148313, 2324522934, 387420489;
%F Formula
The row polynomials satisfy P(n,x) = (1+6*x+9*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[(1 + 6*x + 9*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] = (1 + 6*x + 9*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-4aebfd11077ddb65
  • 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-4aebfd11077ddb65
  • 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-4aebfd11077ddb65

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.