A120910 → D → D

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Submission text ?

Triangle begins:
  0:     0;
  1:     0;
  2:     6;
  3:    36,    18;
  4:   144,   144,     36;
  5:   480,   720,    360,     60;
  6:  1440,  2880,   2160,    720,    90;
  7:  4032, 10080,  10080,   5040,  1260,   126;
  8: 10752, 32256,  40320,  26880, 10080,  2016,  168;
  9: 27648, 96768, 145152, 120960, 60480, 18144, 3024, 216;

The row polynomials satisfy (n-2)*P(n,x) = (2*n+n*x)*P(n-1,x) for n >= 3, with P(0,x) = 0, P(1,x) = 0, P(2,x) = 6.

P[0, x_] := 0;
P[1, x_] := 0;
P[2, x_] := 6;
P[n_, x_] := P[n, x] = Expand[Together[((2*n + n*x)*P[n - 1, x])/(n - 2)]];
Table[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten

P(N) = {my(v = vector(N + 1)); v[1] = 0; v[2] = 0; v[3] = 6; for(n = 3, N, my(i = n + 1); v[i] = ((2*n + n*x)*v[i - 1])/(n - 2)); 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)

Properties

• Real-rooted? Every row P_n, n ≥ 0, is zero or real-rooted with all roots in (−∞, 0]
  by Laguerre’s theorem on differential operators
• Coefficients of one sign? Every nonzero row, n ≥ 0: the coefficients of P_n have one sign
  derived from Laguerre’s theorem on differential operators
• Hadamard kernel (Malo)? Rows P_n, n ≥ 0, are Hadamard kernels (preserve real-rootedness)
  derived from Laguerre’s theorem on differential operators

Proof chains ? JSON

• Laguerre’s theorem on differential operators [SP14] polytool ? step ›

  • from derivative of Triangle read by rows: T(n,k) is the number of ternary words of length n having k levels (n >= 1, 0 <= k …?
    • Laguerre’s theorem on differential operators [SP14] polytool ? step ›

      • from Triangle read by rows: T(n,k) is the number of ternary words of length n having k levels (n >= 1, 0 <= k <= n-1). A lev…?
        • Row-hypergeometric rows (multiplier sequences) [SP14; Bra15, Thm 7.1 of arXiv:1410.6601] polytool RealRooted RealRooted.isPFMultiplierSequence_eval_of_roots_nonpos RealRooted RealRooted.isPFMultiplierSequence_inv_ascPochhammer RealRooted RealRooted.IsPFMultiplierSequence.mul ? step › direct check
        • Liu–Wang theorem [LW07, Thm 2.1, Cor 2.4] ? step › direct check
        • Iterated real-rootedness preservers [SP14; Bra15, Thm 7.1 of arXiv:1410.6601; Bra06, Cor 3.5] polytool ? step › direct check
        • Parent-row provers of polytool polytool ? step › direct check
        • Affine, reversal and Möbius substitutions (elementary) polytool ? step ›

          • from Triangle read by rows: T(n,k) is the number of ternary words of length n having k runs (i.e., subwords of maximal lengt…?
            • Row-hypergeometric rows (multiplier sequences) [SP14; Bra15, Thm 7.1 of arXiv:1410.6601] polytool RealRooted RealRooted.isPFMultiplierSequence_eval_of_roots_nonpos RealRooted RealRooted.isPFMultiplierSequence_inv_ascPochhammer RealRooted RealRooted.IsPFMultiplierSequence.mul ? step › direct check
            • Liu–Wang theorem [LW07, Thm 2.1, Cor 2.4] ? step › direct check
            • Iterated real-rootedness preservers [SP14; Bra15, Thm 7.1 of arXiv:1410.6601; Bra06, Cor 3.5] polytool ? step › direct check
            • Affine, reversal and Möbius substitutions (elementary) polytool ? step ›

              • from Triangle read by rows: T(n,k) is the number of ternary words of length n having k levels (n >= 1, 0 <= k <= n-1). A lev…?
                • ↑ Row-hypergeometric rows (multiplier sequences) (above)
                • ↑ Liu–Wang theorem (above)
                • ↑ Iterated real-rootedness preservers (above)
                • ↑ Parent-row provers of polytool (above)
            • Parent-row provers of polytool polytool ? step › direct check

Related ?

Same fingerprint ?

• A120909 → basis A013610
• A178820 → basis A013609 → basis A013611
• A038330 → basis A013609 → D
• A136572 → θ+1 → basis A013609
• A196347 → basis A013611
• A038325 → basis A013609 → basis A007318
• A134346 → x ↦ x/(x+1)
• A120909 → D
• A038338 → x ↦ x/(x+1)
• A135065 → basis A013611
• A038325 → basis A007318
• basis-map coefficients of A026729 → basis A013609 → reverse
• A085880 → x ↦ x/(x+1)
• A156992 → basis A013611 → D
• A028326 → basis A007318 → reverse
• A013609 → D
• A178821 → basis A013609 → basis A013611
• basis-map coefficients of A112227 → basis A013609
• A094305 → x ↦ x+1
• basis-map coefficients of A113214, shifted → x ↦ x/(x+1)
• A127648 → D → basis A013609
• A085881 → basis A007318
• A120909 → basis A013610 → basis A013610
• A135089 → basis A013611
• A124860 → x ↦ x+1
• A178822 → x ↦ x/(x+1)
• A120909: Triangle read by rows: T(n,k) is the number of ternary words of length n having k runs (i.e., subwords of maxi…
• basis-map coefficients of A026729 → basis A013609 → D
• A196347 → basis A013611 → basis A013610
• A028326 → basis A007318
• basis-map coefficients of A127647 → x ↦ x/(x+1)
• A038330 → basis A013609
• A134059 → basis A013611
• A130123 → basis A013609
• A131431 → θ+1 → basis A013609
• A028326 → basis A013611 → basis A013610
• basis-map coefficients of A026729 → basis A007318 → basis A013611
• A178821 → basis A007318 → reverse
• A085880 → basis A013609 → x ↦ x+1
• A131431 → x ↦ x+1 → basis A013611
• A085880 → basis A013611
• A136521 → basis A013609
• basis-map coefficients of A026729, shifted → basis A007318 → basis A013611
• A178820 → basis A007318
• basis-map coefficients of A026729 → basis A013609
• A038325 → x ↦ x/(x+1)
• basis-map coefficients of A030528, shifted → θ+1 → basis A013609
• A130123 → D → basis A013609
• image under θ+1 → (θ+1)² → basis A013609
• A134346 → basis A013611
• A085881 → basis A007318 → reverse
• A178821 → basis A007318 → D
• A178821 → basis A013611 → D
• A038208 → basis A007318 → D
• A028326 → basis A013611
• basis-map coefficients of A112227 → (θ+1)² → basis A013609
• basis-map coefficients of A026729 → basis A013609 → basis A013610
• A038338 → basis A013609 → basis A007318
• A178821 → x ↦ x/(x+1)
• A136572 → (θ+1)² → basis A013609
• A356546 → x ↦ x+1
• A038208 → basis A007318
• A013609 → basis A013610 → basis A013610
• A178820 → basis A013611
• basis-map coefficients of A112227 → x ↦ x+1 → basis A013611
• A038291 → basis A013609 → basis A013610
• A136572 → basis A013609
• A038325 → basis A007318 → reverse
• A085880 → basis A013611 → basis A013610
• A178822 → basis A013611 → D
• A136572 → basis A013609 → D
• basis-map coefficients of A030528, shifted → basis A013609 → D
• A131431 → D → basis A013609
• A027466 → basis A013611
• A135838 → basis A013611
• basis-map coefficients of A021012 → θ+1 → basis A013609
• A038330 → basis A013609 → reverse
• A038221 → basis A013609 → basis A013611
• A216973 → basis A013611
• A356546 → basis A013611 → D
• A356546 → basis A013609 → basis A013611
• basis-map coefficients of A026729, shifted → basis A013609 → D
• Veronese parent of A098172 → x ↦ x/(x+1)
• A038221 → basis A013611 → basis A013610
• A013609: Triangle of coefficients in expansion of (1+2*x)^n.
• A038338 → x ↦ x+1 → D
• image under θ+1 → θ+1 → D → basis A013609
• A178820 → x ↦ x/(x+1)
• A135065 → x ↦ x+1 → reverse
• basis-map coefficients of A026729, shifted → basis A007318 → x ↦ x+1
• A156992 → basis A013611 → basis A013610
• A156992 → basis A013611
• A344565 → x ↦ x/(x+1)
• A136572 → basis A013609 → basis A013610
• A085881 → basis A013611
• A094305 → x ↦ x+1 → D
• A028326 → basis A013609 → basis A013611
• A178822 → basis A013611 → basis A013610
• A134346 → x ↦ x+1
• A038325 → basis A007318 → D
• A178821 → basis A013611 → reverse
• A085880 → x ↦ x+1 → reverse
• A038221 → basis A013611
• A344565 → basis A007318
• image under θ+1 → basis A013609
• A196347 → x ↦ x+1
• A376827 → basis A013611
• A178822 → x ↦ x+1 → D
• A085880 → basis A013611 → D
• A356546 → x ↦ x/(x+1)
• A038329 → x ↦ x+1 → basis A013610
• A178822 → basis A013609 → basis A013611
• Veronese parent of A098172 → x ↦ x/(x+1)
• A356546 → basis A013611
• basis-map coefficients of A127647 → basis A007318
• A038208 → x ↦ x/(x+1)
• A178822 → x ↦ x+1
• basis-map coefficients of A030528, shifted → basis A013609 → basis A013610
• basis-map coefficients of A112227 → x ↦ x+1 → basis A007318
• A120910 → basis A007318 → basis A013609
• Veronese parent of A098172 → x ↦ x/(x+1)
• A356546 → x ↦ x+1 → D
• A094305 → x ↦ x/(x+1)
• A376827 → x ↦ x/(x+1)
• A085881 → basis A013611 → basis A013610
• A120910 → D
• A258758 → basis A013611
• A156992 → basis A007318
• A156992 → basis A013609 → basis A007318
• basis-map coefficients of A021012 → basis A013609
• A085880 → D → basis A013611
• A085881 → x ↦ x/(x+1)
• basis-map coefficients of A026729 → (θ+1)² → basis A013609
• A135089 → basis A007318
• A003506 → x ↦ x+1
• A178821 → basis A007318
• basis-map coefficients of A030528, shifted → D → basis A013609
• A178821 → basis A013611
• A156992 → x ↦ x/(x+1)
• A003506 → D → basis A013611
• A196347 → basis A013611 → D
• A178822 → basis A013609 → x ↦ x+1
• A038221 → basis A013611 → D
• basis-map coefficients of A026729, shifted → (θ+1)² → basis A013609
• A178820 → basis A013611 → reverse
• basis-map coefficients of A113214, shifted → basis A013609 → basis A013611
• A134059 → basis A007318
• A147716 → basis A013610 → basis A013610
• A085880 → x ↦ x+1
• A135838 → x ↦ x/(x+1)
• A085880 → basis A013609 → basis A013611
• A120909 → basis A013610 → D
• A038221 → x ↦ x+1
• A196347 → basis A013609 → basis A007318
• basis-map coefficients of A127647 → basis A013611
• A132200 → basis A007318
• A120910 → basis A013610 → basis A013611
• A120909 → basis A013610 → reverse
• A028326 → basis A007318 → D
• basis-map coefficients of A026729, shifted → θ+1 → basis A013609
• A013609 → D → D
• basis-map coefficients of A112227 → θ+1 → basis A013609
• A178820 → basis A013611 → basis A013610
• basis-map coefficients of A026729, shifted → D → basis A013609
• A038330 → basis A013611 → basis A007318
• basis-map coefficients of A026729 → D → basis A013609
• A135065 → x ↦ x/(x+1)
• A085881 → basis A007318 → D
• A038221 → x ↦ x+1 → D
• A038208 → basis A013611
• A013609 → basis A013610
• A134058 → basis A007318
• A028326 → basis A013611 → D
• A356546 → x ↦ x+1 → reverse
• A134309 → basis A013609
• basis-map coefficients of A113214, shifted → D → basis A007318
• A356546 → basis A013611 → reverse
• A085881 → basis A013611 → reverse
• A038330 → basis A013611 → x ↦ x/(x+1)
• A027465 → basis A013611 → basis A013611
• A085880 → D → basis A007318
• A178820 → basis A007318 → reverse
• A132440 → θ+1 → basis A013609
• basis-map coefficients of A113214, shifted → basis A013611
• A038338 → basis A013611
• A356546 → basis A013611 → basis A013610
• A178820 → basis A013611 → D
• A344565 → basis A013611
• A028326 → x ↦ x/(x+1)
• A131431 → basis A013609
• A135065 → x ↦ x+1
• basis-map coefficients of A112227 → basis A013609 → basis A013610
• A120910: Triangle read by rows: T(n,k) is the number of ternary words of length n having k levels (n >= 1, 0 <= k <= n-…
• A178821 → basis A013611 → basis A013610
• A178820 → basis A007318 → D
• A130123 → basis A013609 → D
• A196347 → x ↦ x+1 → D
• A003506 → x ↦ x/(x+1)
• A124860 → x ↦ x/(x+1)
• A159854 → x ↦ x/(x+1)
• basis-map coefficients of A113214, shifted → x ↦ x+1
• A007318 → ×(−(1/2)n+(1/2)n²) → x ↦ x+1
• A130123 → θ+1 → basis A013609
• A038338 → x ↦ x+1
• A027465 → D → basis A013609
• A038208 → D → basis A013611
• basis-map coefficients of A112227 → basis A013609 → D
• A038207: Triangle whose (i,j)-th entry is binomial(i,j)*2^(i-j).
• A135838 → x ↦ x+1
• A258758 → basis A007318
• A135065 → x ↦ x+1 → D
• A129186 → basis A013609
• basis-map coefficients of A026729, shifted → basis A013609 → basis A013610
• A131431 → x ↦ x+1 → basis A007318
• A038325 → basis A013611
• basis-map coefficients of A030528, shifted → (θ+1)² → basis A013609
• A178822 → basis A013611
• A131431 → x ↦ x+1 → x ↦ x/(x+1)
• A013609 → D → basis A013610
• A136572 → D → basis A013609
• A132440 → basis A013609
• A132200 → basis A013611
• A085881 → basis A013611 → D
• A131436 → basis A013609
• A013609 → basis A013610 → D
• A007318 → ×(−(1/2)n+(1/2)n²) → x ↦ x/(x+1)
• A178822 → x ↦ x+1 → reverse
• basis-map coefficients of A026729, shifted → basis A013609
• basis-map coefficients of A113214, shifted → D → basis A013611
• A094305 → x ↦ x+1 → reverse
• A038208 → basis A013611 → D
• A038338 → x ↦ x+1 → reverse
• basis-map coefficients of A113214, shifted → basis A013609 → x ↦ x+1
• A028326 → basis A013609 → x ↦ x+1
• A027466 → basis A013611 → D
• basis-map coefficients of A030528, shifted → basis A013609
• A003506 → D → x ↦ x+1
• A134058 → basis A013611
• A156992 → basis A007318 → D
• A094305 → basis A013611
• A124860 → basis A013611
• A376827 → basis A007318

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.