A038334 → x ↦ x+1 → D

nonnegative coefficientsonly rational roots

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

Recurrence

\(\left(1 + n\right)\,P_{n}(x) = \left(40 + 16\,x + 20\,n + 8\,n x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 320 + 128\,x\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14x15Pn(1)
0320128448
196007680153618816
225600030720012288016384702464
36400000102400006144000163840016384024586240
415360000030720000024576000098304000196608001572864826097664
5358400000086016000008601600000458752000013762560002202009601468006426985857024
68192000000022937600000027525120000018350080000073400320000176160768002348810240134217728863547424768
718432000000005898240000000825753600000066060288000003303014400000105696460800021139292160024159191040120795955227201743880192
8409600000000001474560000000002359296000000002202009600000001321205760000005284823040000014092861440000241591910400024159191040010737418240846276476272640
9901120000000000360448000000000064880640000000006920601600000000484442112000000023253221376000007751073792000001771674009600002657511014400023622320128009448928051226065315469197312
101966080000000000086507520000000000173015040000000000207618048000000000166094438400000000930128855040000003720515420160000010630044057600000212600881152000028346784153600022677427322880824633720832796176908877299712
11425984000000000000204472320000000000044983910400000000005997854720000000000539806924800000000034547643187200000001612223348736000000552762290995200000138190572748800000245672129331200002948065551974400214404767416320714682558054424150699569278091264
1291750400000000000004771020800000000000011450449920000000000016793993216000000000016793993216000000000012091675115520000000064488933949440000000257955735797760000007738672073932800000171970490531840000027515278485094400030016667438284800200111116255232061572651155456728236479319770136576
1319660800000000000000011010048000000000000002862612480000000000000458017996800000000000050381979648000000000004030558371840000000000241833502310400000000011055245819904000000003869336036966400000001031822943191040000002063645886382080000030016667438284800003001666743828480001847179534663680052776558133248021847094379593104097280
1441943040000000000000002516582400000000000000070464307200000000000000122138132480000000000000146565758976000000000000128977867898880000000000859852452659200000000004422098327961600000000017688393311846400000000550305569701888000000013207333672845312000002401333395062784000003201777860083712000029554872554618880001688849860263936004503599627370496652499885470514042372096
Technical details
Node id
n-dfc1be3375cc826d · revision 0 · JSON
Definition source
derived:derivative
Fingerprint
f6-9629d1e9c04dbfbe

Observed on the stored rows ?

  • Degrees: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 (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 = 0, …, ascending powers of x
%e Example
Triangle begins:
  0:             320,              128;
  1:            9600,             7680,             1536;
  2:          256000,           307200,           122880,            16384;
  3:         6400000,         10240000,          6144000,          1638400,           163840;
  4:       153600000,        307200000,        245760000,         98304000,         19660800,          1572864;
  5:      3584000000,       8601600000,       8601600000,       4587520000,       1376256000,        220200960,        14680064;
  6:     81920000000,     229376000000,     275251200000,     183500800000,      73400320000,      17616076800,      2348810240,       134217728;
  7:   1843200000000,    5898240000000,    8257536000000,    6606028800000,    3303014400000,    1056964608000,    211392921600,     24159191040,     1207959552;
  8:  40960000000000,  147456000000000,  235929600000000,  220200960000000,  132120576000000,   52848230400000,  14092861440000,   2415919104000,   241591910400,   10737418240;
  9: 901120000000000, 3604480000000000, 6488064000000000, 6920601600000000, 4844421120000000, 2325322137600000, 775107379200000, 177167400960000, 26575110144000, 2362232012800, 94489280512;
%F Formula
The row polynomials satisfy (n+1)*P(n,x) = (20*n+40+(8*n+16)*x)*P(n-1,x) for n >= 1, with P(0,x) = 320 + 128*x.
%t Mathematica
P[0, x_] := 320 + 128*x;
P[n_, x_] := P[n, x] = Expand[Together[((20*n + 40 + (8*n + 16)*x)*P[n - 1, x])/(n + 1)]];
Table[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten
%o PARI/GP
P(N) = {my(v = vector(N + 1)); v[1] = 320 + 128*x; for(n = 1, N, my(i = n + 1); v[i] = ((20*n + 40 + (8*n + 16)*x)*v[i - 1])/(n + 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.