basis-map coefficients of A112227 → basis A013610 → basis A013609

nonnegative coefficientsonly rational roots

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

Recurrence

\(P_{n}(x) = \left(4 + 6\,x\right)\,P_{n-1}(x)\)
\(P_{1}(x) = 16 + 48\,x + 36\,x^{2}\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9Pn(1)
1164836100
2642884322161000
3256153634563456129610000
4102476802304034560259207776100000
5409636864138240276480311040186624466561000000
616384172032774144193536029030402612736130636827993610000000
76553678643241287681238630423224320278691842090188889579521679616100000000
82621443538944212336647431782416721510425082265625082265616124313660466176100776961000000000
Technical details
Node id
n-c79eb849b59e8079 · revision 0 · JSON
Definition source
derived:basis_map_A013609
Fingerprint
f6-f06e51c139cfae05

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 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:      16,       48,        36;
   2:      64,      288,       432,        216;
   3:     256,     1536,      3456,       3456,       1296;
   4:    1024,     7680,     23040,      34560,      25920,        7776;
   5:    4096,    36864,    138240,     276480,     311040,      186624,       46656;
   6:   16384,   172032,    774144,    1935360,    2903040,     2612736,     1306368,      279936;
   7:   65536,   786432,   4128768,   12386304,   23224320,    27869184,    20901888,     8957952,     1679616;
   8:  262144,  3538944,  21233664,   74317824,  167215104,   250822656,   250822656,   161243136,    60466176,   10077696;
   9: 1048576, 15728640, 106168320,  424673280, 1114767360,  2006581248,  2508226560,  2149908480,  1209323520,  403107840,   60466176;
  10: 4194304, 69206016, 519045120, 2335703040, 7007109120, 14714929152, 22072393728, 23648993280, 17736744960, 8868372480, 2660511744, 362797056;
%F Formula
The row polynomials satisfy P(n,x) = (4+6*x)*P(n-1,x) for n >= 2, with P(1,x) = 16 + 48*x + 36*x^2.
%t Mathematica
P[1, x_] := 16 + 48*x + 36*x^2;
P[n_, x_] := P[n, x] = Expand[(4 + 6*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] = 16 + 48*x + 36*x^2; for(n = 2, N, my(i = n); v[i] = (4 + 6*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.