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A191290
Increasing sequence generated by these rules: a(1)=1, and if x is in a then 2x+1 and x(x+1)/2 are in a.
2
1, 3, 6, 7, 13, 15, 21, 27, 28, 31, 43, 55, 57, 63, 87, 91, 111, 115, 120, 127, 175, 183, 223, 231, 241, 255, 351, 367, 378, 406, 447, 463, 483, 496, 511, 703, 735, 757, 813, 895, 927, 946, 967, 993, 1023, 1407, 1471, 1515, 1540, 1627, 1653, 1791, 1855, 1893, 1935, 1987, 2016, 2047, 2815, 2943, 3031, 3081, 3255, 3307, 3583
OFFSET
1,2
COMMENTS
See A191203.
LINKS
EXAMPLE
1 -> 3 -> 6,7 -> 13,15,21,28 ->
MATHEMATICA
g=11; Union[Flatten[NestList[{1+2#, (#^2+#)/2} &, 1, g]]]
(* A191290; use g>9 to get all of first 60 terms *)
CROSSREFS
Cf. A191203.
Sequence in context: A282354 A088146 A176301 * A137595 A033053 A248388
KEYWORD
nonn
AUTHOR
Clark Kimberling, May 29 2011
STATUS
approved