A249059 Row sums of the triangular array at A249057.

1, 5, 10, 40, 110, 430, 1420, 5720, 21340, 89980, 367400, 1627120, 7138120, 33172040, 154520080, 751616800, 3687498320, 18719834320, 96157299040, 507993654080, 2719611532000, 14911459229920, 82901747529920, 470599687507840, 2708946870815680

Offset

0,2

Links

Clark Kimberling, Table of n, a(n) for n = 0..100

Example

First 3 rows from A249057:
1
4    1
5    4    1,
so that a(0) = 1, a(1) = 5, a(2) = 10.

Mathematica

z = 30; p[x_, n_] := x + (n + 2)/p[x, n - 1]; p[x_, 1] = 1;
t = Table[Factor[p[x, n]], {n, 1, z}];
u = Numerator[t];
v1 = Flatten[CoefficientList[u, x]]; (* A249057  *)
v2 = u /. x -> 1  (* A249059 *)
v3 = u /. x -> 0  (* A249060 *)

Crossrefs

Cf. A249057, A249060.

Sequence in context: A191580 A179306 A117865 * A163305 A001692 A038070

Adjacent sequences: A249056 A249057 A249058 * A249060 A249061 A249062

Keyword

nonn,easy

Author

Clark Kimberling, Oct 20 2014

Status

approved