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A249059 Row sums of the triangular array at A249057. 4
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified October 18 16:09 EDT 2018. Contains 316323 sequences. (Running on oeis4.)