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A209165
Triangle of coefficients of polynomials v(n,x) jointly generated with A209164; see the Formula section.
3
1, 3, 1, 6, 4, 1, 12, 14, 7, 1, 24, 40, 28, 8, 1, 48, 104, 96, 44, 11, 1, 96, 256, 296, 184, 66, 12, 1, 192, 608, 848, 664, 316, 90, 15, 1, 384, 1408, 2304, 2176, 1296, 496, 120, 16, 1, 768, 3200, 6016, 6656, 4768, 2288, 736, 152, 19, 1, 1536, 7168, 15232
OFFSET
1,2
COMMENTS
Alternating row sums: 1,2,3,4,5,6,7,8,9,10,11,...
For a discussion and guide to related arrays, see A208510.
FORMULA
u(n,x)=u(n-1,x)+(x+1)*v(n-1,x),
v(n,x)=(x+1)*u(n-1,x)+v(n-1,x)+1,
where u(1,x)=1, v(1,x)=1.
EXAMPLE
First five rows:
1
3....1
6....4....1
12...14...7....1
24...40...28...8...1
First three polynomials v(n,x): 1, 3 + x, 6 + 4x + x^2.
MATHEMATICA
u[1, x_] := 1; v[1, x_] := 1; z = 16;
u[n_, x_] := u[n - 1, x] + (x + 1)*v[n - 1, x];
v[n_, x_] := (x + 1)*u[n - 1, x] + v[n - 1, x] + 1;
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[%] (* A209164 *)
Table[Expand[v[n, x]], {n, 1, z}]
cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
TableForm[cv]
Flatten[%] (* A209165 *)
CROSSREFS
Sequence in context: A131415 A210230 A207615 * A121437 A078585 A116551
KEYWORD
nonn,tabl
AUTHOR
Clark Kimberling, Mar 08 2012
STATUS
approved