

A191920


Ordered sums f+3g, where f and g are Lucas numbers (A000032 beginning at 1).


4



4, 6, 7, 10, 12, 13, 14, 15, 16, 19, 20, 21, 22, 23, 24, 25, 27, 28, 30, 32, 34, 36, 37, 38, 39, 40, 41, 44, 50, 51, 55, 56, 57, 58, 59, 61, 62, 65, 68, 72, 79, 80, 83, 85, 88, 90, 91, 94, 97, 98, 101, 105, 109, 116, 126, 130, 132, 134, 135, 142, 144, 145
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OFFSET

1,1


LINKS

Table of n, a(n) for n=1..62.


MATHEMATICA

c = 1; d = 3; f[n_] := LucasL[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]] (* A191920 *)
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]] (*A 191921: c*f(i)d*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]] (* A191922: d*f(i)c*f(j) *)
v3 = Union[v1, v2] (* A191923 *)


CROSSREFS

Cf. A191921, A191922, A191923, A191842.
Sequence in context: A080641 A272632 A229744 * A047234 A089532 A285254
Adjacent sequences: A191917 A191918 A191919 * A191921 A191922 A191923


KEYWORD

nonn


AUTHOR

Clark Kimberling, Jun 19 2011


STATUS

approved



