

A191838


Ordered sums f+2*g, where f and g are positive Fibonacci numbers (A000045).


5



3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 17, 18, 19, 21, 23, 24, 25, 27, 28, 29, 31, 34, 36, 37, 38, 39, 40, 43, 44, 45, 47, 50, 55, 57, 59, 60, 61, 63, 65, 69, 70, 71, 73, 76, 81, 89, 91, 93, 95, 97, 99, 102, 105, 111, 112, 113, 115, 118, 123, 131, 144
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OFFSET

1,1


LINKS

Table of n, a(n) for n=1..64.


MATHEMATICA

c = 1; d = 2; f[n_] := Fibonacci[n];
g[n_] := c*f[n]; h[n_] := d*f[n];
t[i_, j_] := h[i] + g[j];
u = Table[t[i, j], {i, 1, 20}, {j, 1, 20}];
v = Union[Flatten[u ]] (* A191838 *)
t1[i_, j_] := If[g[i]  h[j] > 0, g[i]  h[j], 0]
u1 = Table[t1[i, j], {i, 1, 20}, {j, 1, 20}];
v1 = Union[Flatten[u1 ]] (* A191839: f(i)2*f(j) *)
g1[n_] := d*f[n]; h1[n_] := c*f[n];
t2[i_, j_] := If[g1[i]  h1[j] > 0, g1[i]  h1[j], 0]
u2 = Table[t2[i, j], {i, 1, 20}, {j, 1, 20}];
v2 = Union[Flatten[u2 ]] (* A191840: 2*f(i)f(j) *)
v3 = Union[v1, v2] (* A191841 *)
With[{nn=20}, Take[Union[#[[1]]+2#[[2]]&/@Tuples[Fibonacci[ Range[20]], 2]], 4nn]] (* Harvey P. Dale, Jun 08 2015 *)


CROSSREFS

Cf. A191839, A191840, A191841.
Sequence in context: A192452 A132147 A118955 * A333214 A108473 A298113
Adjacent sequences: A191835 A191836 A191837 * A191839 A191840 A191841


KEYWORD

nonn


AUTHOR

Clark Kimberling, Jun 17 2011


STATUS

approved



