A178820 → basis A007318 → basis A013611

nonnegative coefficientsonly rational roots

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

Recurrence

\(\left(n\right)\,P_{n}(x) = \left(9 + 12\,x + 3\,n + 4\,n x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
011
1121628
290240160490
35402160288012806860
42835151203024026880896084035
5136089072024192032256021504057344941192
66123648988816329602903040290304015482883440649882516
72624402449440979776021772800290304002322432010321920196608098825160
8108256511547360538876801437004802395008002554675201703116806488064010813440951192165
94330260519631202771366408622028801724405760229920768020437401601167851520389283840576716808877793540
101688801422517352013510411204803701760112086374401793381990419926466560151820697607591034880224919552029989273680787921214
11644815089457287846304858560252194342406725182464012553673932816738231910415941173248010627448832047233105920125954949121526726656719746934452
122418056553868890480283718635201260971712003782915136008070218956801255367393280143470559232011955879936007084965888002833986355206870269952076336332806297785676455
138928208801547556192012380449536060526642176020175547392004842131374080860823355392011477644738560114776447385608501959065600453437816832016488647884803664143974403758096384054257845827920
143252418920607118198405261691052802806235228160102895291699202743874445312054877488906240836228402380809755998027776086719982469120578133216460802803070140416093435671347201916629155840182536110080461191689537320
Technical details
Node id
n-b75602a185bd3461 · revision 0 · JSON
Definition source
derived:basis_map_A013611
Fingerprint
f6-c91d5d506c107735

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 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

Matches ?

No OEIS matches.

Submission text ?

Atlas rows n = 0, …, ascending powers of x
%e Example
Triangle begins:
  0:       1;
  1:      12,       16;
  2:      90,      240,       160;
  3:     540,     2160,      2880,      1280;
  4:    2835,    15120,     30240,     26880,       8960;
  5:   13608,    90720,    241920,    322560,     215040,      57344;
  6:   61236,   489888,   1632960,   2903040,    2903040,    1548288,     344064;
  7:  262440,  2449440,   9797760,  21772800,   29030400,   23224320,   10321920,    1966080;
  8: 1082565, 11547360,  53887680, 143700480,  239500800,  255467520,  170311680,   64880640,  10813440;
  9: 4330260, 51963120, 277136640, 862202880, 1724405760, 2299207680, 2043740160, 1167851520, 389283840, 57671680;
%F Formula
The row polynomials satisfy n*P(n,x) = (3*n+9+(4*n+12)*x)*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[Together[((3*n + 9 + (4*n + 12)*x)*P[n - 1, x])/(n)]];
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] = ((3*n + 9 + (4*n + 12)*x)*v[i - 1])/(n)); 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.