basis-map coefficients of A026729 → basis A013610 → basis A013610

nonnegative coefficientsonly rational roots

Proved for all n all roots real, in (−∞, 0]coefficients of one signHadamard kernel

Recurrence

\(P_{n}(x) = \left(4 + 9\,x\right)\,P_{n-1}(x)\)
\(P_{1}(x) = 1\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
111
24913
3167281169
4644329727292197
52562304777611664656128561
61024115205184011664013122059049371293
7409655296311040933120157464014171765314414826809
81638425804817418246531840146966401984046414880348478296962748517
965536117964892897284180377611757312021163161623808556815305500843046721815730721
10262144530841647775744250822656846526464190468454428570268162754990144154968195638742048910604499373
111048576235929602388787201433272320564350976015237476352285702681603673320192030993639120154968195603486784401137858491849
1241943041038090241167851520788299776035473489920111741493248251418359808404065221120454573373760340930030320153418513644313810596091792160394037
131677721645298483256056872964204265472021284093952076622738227220113468784643879026122752545488048512054548804851203682044327456150629086123228242953648123298085122481
146710886419629342722649961267221862180454412297476505604980477984768149414339543043361822639718456730757045248709134463065606382210167590439163562392032146863358970122541865828329302875106592253
1526843545684557168641236648591361112983732224688658684313630989640794112104590037680128268945811177472529487065755648794230598633472893509423462656731053164651264411217405116336142344486386424228767924549613937376385699289
Technical details
Node id
n-0eaafea67493c217 · revision 0 · JSON
Definition source
derived:basis_map_A013610
Fingerprint
f6-12e1fe8c90bb4450

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 -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 Example
Triangle begins:
   1:      1;
   2:      4,       9;
   3:     16,      72,       81;
   4:     64,     432,      972,       729;
   5:    256,    2304,     7776,     11664,      6561;
   6:   1024,   11520,    51840,    116640,    131220,      59049;
   7:   4096,   55296,   311040,    933120,   1574640,    1417176,     531441;
   8:  16384,  258048,  1741824,   6531840,  14696640,   19840464,   14880348,    4782969;
   9:  65536, 1179648,  9289728,  41803776, 117573120,  211631616,  238085568,  153055008,   43046721;
  10: 262144, 5308416, 47775744, 250822656, 846526464, 1904684544, 2857026816, 2754990144, 1549681956, 387420489;
%F Formula
The row polynomials satisfy P(n,x) = (4+9*x)*P(n-1,x) for n >= 2, with P(1,x) = 1.
%t Mathematica
P[1, x_] := 1;
P[n_, x_] := P[n, x] = Expand[(4 + 9*x)*P[n - 1, x]];
Table[CoefficientList[P[n, x], x], {n, 1, 10}] // Flatten
%o PARI/GP
P(N) = {my(v = vector(N)); v[1] = 1; for(n = 2, N, my(i = n); v[i] = (4 + 9*x)*v[i - 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

Proof chains ? JSON

Same fingerprint ?

References

  1. [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
  2. [Bra15] Petter Brändén. Unimodality, log-concavity, real-rootedness and beyond. Handbook of enumerative combinatorics, :437–483, March 2015. doi:10.1201/b18255-10
  3. [SP14] J Schur and G Polya. Über zwei Arten von Faktorenfolgen in der Theorie der algebraischen Gleichungen. J. Reine Angew. Math., 1914.