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Monotonically ordered sums 2^(i-1)+3*2^(j-1), for i>=1, j>=1.
4

%I #5 Mar 30 2012 18:57:33

%S 4,5,7,8,10,11,13,14,16,19,20,22,25,26,28,32,35,38,40,44,49,50,52,56,

%T 64,67,70,76,80,88,97,98,100,104,112,128,131,134,140,152,160,176,193,

%U 194,196,200,208,224,256,259,262,268,280,304,320,352,385,386,388

%N Monotonically ordered sums 2^(i-1)+3*2^(j-1), for i>=1, j>=1.

%t c = 1; d = 3; f[n_] := 2^(n - 1);

%t g[n_] := c*f[n]; h[n_] := d*f[n];

%t t[i_, j_] := h[i] + g[j]

%t u = Table[t[i, j], {i, 1, 20}, {j, 1, 20}];

%t v = Union[Flatten[u ]] (* A191984 *)

%t t1[i_, j_] := If[g[i] - h[j] > 0, g[i] - h[j], 0]

%t u1 = Table[t1[i, j], {i, 1, 20}, {j, 1, 20}];

%t v1 = Union[Flatten[u1 ]] (* A191985; c*f(i)-d*f(j) *)

%t c1 = d; d1 = c;

%t g1[n_] := d*f[n]; h1[n_] := c*f[n];

%t t2[i_, j_] := If[g1[i] - h1[j] > 0, g1[i] - h1[j], 0]

%t u2 = Table[t2[i, j], {i, 1, 20}, {j, 1, 20}];

%t v2 = Union[Flatten[u2 ]] (* A191986; d*f(i)-c*f(j) *)

%t v3 = Union[v1, v2] (* A191987 *)

%Y Cf. A191985, A191986, A191987.

%K nonn

%O 1,1

%A _Clark Kimberling_, Jun 22 2011