cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A210800 Triangle of coefficients of polynomials v(n,x) jointly generated with A210799; see the Formula section.

Original entry on oeis.org

1, 1, 2, 5, 4, 3, 5, 14, 9, 5, 17, 28, 36, 19, 8, 17, 70, 88, 83, 38, 13, 53, 136, 251, 245, 181, 73, 21, 53, 298, 557, 746, 613, 379, 137, 34, 161, 568, 1376, 1930, 2030, 1439, 769, 252, 55, 161, 1162, 2888, 5026, 5818, 5139, 3221, 1524, 457, 89, 485
Offset: 1

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Author

Clark Kimberling, Mar 27 2012

Keywords

Comments

Row n starts a term of A048473 and ends with F(n+1), where F=A000045 (Fibonacci numbers).
Alternating row sums: 1,2,3,4,5,6,7,...
For a discussion and guide to related arrays, see A208510.

Examples

			First five rows:
1
1....2
5....4....3
5....14...9....5
17...28...36...19...8
First three polynomials v(n,x): 1, 1 + 2x, 5 + 4x + 3x^2
		

Crossrefs

Programs

  • Mathematica
    u[1, x_] := 1; v[1, x_] := 1; z = 16;
    u[n_, x_] := u[n - 1, x] + (x + j)*v[n - 1, x] + c;
    d[x_] := h + x; e[x_] := p + x;
    v[n_, x_] := d[x]*u[n - 1, x] + e[x]*v[n - 1, x] + f;
    j = 1; c = 1; h = 2; p = -1; f = 0;
    Table[Expand[u[n, x]], {n, 1, z/2}]
    Table[Expand[v[n, x]], {n, 1, z/2}]
    cu = Table[CoefficientList[u[n, x], x], {n, 1, z}];
    TableForm[cu]
    Flatten[%]   (* A210799 *)
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]   (* A210800 *)

Formula

u(n,x)=u(n-1,x)+(x+1)*v(n-1,x),
v(n,x)=(x+2)*u(n-1,x)+(x-1)*v(n-1,x),
where u(1,x)=1, v(1,x)=1.
T(n,k) = T(n-1,k-1) + 3*T(n-2,k) + 2*T(n-2,k-1) + T(n-2,k-2) + a(k) with a(0) = 2, a(1) = 1, a(k) = 0 if k>1, T(1,0) = T(2,0) = 1, T(2,1) = 2 and T(n,k) = 0 if k<0 or if k >n. - Philippe Deléham, Mar 31 2012