A290319 → basis A013611 → x ↦ x+1

nonnegative coefficientsonly rational roots

Proved for all n all roots real, in (−∞, −1]coefficients of one signHadamard kernelinterlacing (weak)

Recurrence

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

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
011
16410
2606416140
38401136480642520
4151202380813184307225655440
53326405842563852801203201792010241441440
686486401652121612354304466944094720098304409643243200
7259459200530231040436713984189500416470937606737920516096163841470268800
888216128001906569216016969199616818987008023591895044174643204449894426214406553655870214400
9335221286400759782753280721092354048379091861504122408681472253004021763360817152277610496129761282621442346549004800
101407929402880033251760783360333250098831361880622759936066575320678401552251617280242355929088251029094401655439360629145601048576107941254220800
116476475253248001585898172149760166595749775769699838650910310438147138551808098033702666240173573792071682124157550592176561848320951582720029989273641943045397062711040000
1232382376266240000818854987087872008964146757648384056583155446185984230671153123164166427570675384320126000377102336017563739435827217324722618368118203875328053057945600140928614416777216291441386396160000
131748648318376960000455134643533946880051681812439652761603414056264399978496147195684864983040043935727772001894493750486336798720145244343794401281638084598824960133128983150592759328407552028833323417665431142406710886416903600410977280000
1410142160246586368000027097268652319703040031795989789134389248021868798831105985740899029722279290077184313705495023604203527194957318414401536121741913935472230415310664424960819214273819418034176972926408982528470964638842881532833562624300647710722684354561048023225480591360000
Technical details
Node id
n-cf5d6ef2e8520cdb · revision 0 · JSON
Definition source
derived:shift_x_plus_one
Fingerprint
f6-1840f5afd9477abc

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:            6,            4;
  2:           60,           64,           16;
  3:          840,         1136,          480,           64;
  4:        15120,        23808,        13184,         3072,          256;
  5:       332640,       584256,       385280,       120320,        17920,        1024;
  6:      8648640,     16521216,     12354304,      4669440,       947200,       98304,       4096;
  7:    259459200,    530231040,    436713984,    189500416,     47093760,     6737920,     516096,     16384;
  8:   8821612800,  19065692160,  16969199616,   8189870080,   2359189504,   417464320,   44498944,   2621440,    65536;
  9: 335221286400, 759782753280, 721092354048, 379091861504, 122408681472, 25300402176, 3360817152, 277610496, 12976128, 262144;
%F Formula
The row polynomials satisfy P(n,x) = (4*n+2+4*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[(4*n + 2 + 4*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] = 1; for(n = 1, N, my(i = n + 1); v[i] = (4*n + 2 + 4*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.