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Row sums of the triangular array at A249057.
4

%I #7 Oct 27 2014 23:56:57

%S 1,5,10,40,110,430,1420,5720,21340,89980,367400,1627120,7138120,

%T 33172040,154520080,751616800,3687498320,18719834320,96157299040,

%U 507993654080,2719611532000,14911459229920,82901747529920,470599687507840,2708946870815680

%N Row sums of the triangular array at A249057.

%H Clark Kimberling, <a href="/A249059/b249059.txt">Table of n, a(n) for n = 0..100</a>

%e First 3 rows from A249057:

%e 1

%e 4 1

%e 5 4 1,

%e so that a(0) = 1, a(1) = 5, a(2) = 10.

%t z = 30; p[x_, n_] := x + (n + 2)/p[x, n - 1]; p[x_, 1] = 1;

%t t = Table[Factor[p[x, n]], {n, 1, z}];

%t u = Numerator[t];

%t v1 = Flatten[CoefficientList[u, x]]; (* A249057 *)

%t v2 = u /. x -> 1 (* A249059 *)

%t v3 = u /. x -> 0 (* A249060 *)

%Y Cf. A249057, A249060.

%K nonn,easy

%O 0,2

%A _Clark Kimberling_, Oct 20 2014