A038330 → basis A013611 → basis A013609

palindromicγ-positivenonnegative coefficientsonly rational roots

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

Recurrence

\(P_{n}(x) = \left(32 + 32\,x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1024 + 2048\,x + 1024\,x^{2}\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9Pn(1)
01024204810244096
132768983049830432768262144
21048576419430462914564194304104857616777216
333554432167772160335544320335544320167772160335544321073741824
4107374182464424509441610612736021474836480161061273606442450944107374182468719476736
53435973836824051816857672155450572812025908428801202590842880721554505728240518168576343597383684398046511104
610995116277768796093022208307863255777286157265115545676965813944320615726511554563078632557772887960930222081099511627776281474976710656
7351843720888323166593487994881266637395197952295548725546188844332308831928324433230883192832295548725546188812666373951979523166593487994883518437208883218014398509481984
Technical details
Node id
n-2115d37162e28af0 · revision 0 · JSON
Definition source
derived:basis_map_A013609
Fingerprint
f6-77a7ed3b1d5f257e

Observed on the stored rows ?

  • Degrees: 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 (affine: slope 1, intercept 2)
  • Palindromic rows: yes
  • γ-positive (gamma_positive): yes
  • 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 = 0, …, ascending powers of x
%e Example
Triangle begins:
  0:              1024,               2048,                1024;
  1:             32768,              98304,               98304,               32768;
  2:           1048576,            4194304,             6291456,             4194304,              1048576;
  3:          33554432,          167772160,           335544320,           335544320,            167772160,             33554432;
  4:        1073741824,         6442450944,         16106127360,         21474836480,          16106127360,           6442450944,           1073741824;
  5:       34359738368,       240518168576,        721554505728,       1202590842880,        1202590842880,         721554505728,         240518168576,          34359738368;
  6:     1099511627776,      8796093022208,      30786325577728,      61572651155456,       76965813944320,       61572651155456,       30786325577728,        8796093022208,       1099511627776;
  7:    35184372088832,    316659348799488,    1266637395197952,    2955487255461888,     4433230883192832,     4433230883192832,     2955487255461888,     1266637395197952,     316659348799488,      35184372088832;
  8:  1125899906842624,  11258999068426240,   50665495807918080,  135107988821114880,   236438980436951040,   283726776524341248,   236438980436951040,   135107988821114880,   50665495807918080,   11258999068426240,   1125899906842624;
  9: 36028797018963968, 396316767208603648, 1981583836043018240, 5944751508129054720, 11889503016258109440, 16645304222761353216, 16645304222761353216, 11889503016258109440, 5944751508129054720, 1981583836043018240, 396316767208603648, 36028797018963968;
%F Formula
The row polynomials satisfy P(n,x) = (32+32*x)*P(n-1,x) for n >= 1, with P(0,x) = 1024 + 2048*x + 1024*x^2.
%t Mathematica
P[0, x_] := 1024 + 2048*x + 1024*x^2;
P[n_, x_] := P[n, x] = Expand[(32 + 32*x)*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] = 1024 + 2048*x + 1024*x^2; for(n = 1, N, my(i = n + 1); v[i] = (32 + 32*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 - 1, v[i])))};
T(9)

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. [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
  4. [SP14] J Schur and G Polya. Über zwei Arten von Faktorenfolgen in der Theorie der algebraischen Gleichungen. J. Reine Angew. Math., 1914.