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A191211
Increasing sequence generated by these rules: a(1)=1, and if x is in a then 1+2x and 1+x^2 are in a.
2
1, 2, 3, 5, 7, 10, 11, 15, 21, 23, 26, 31, 43, 47, 50, 53, 63, 87, 95, 101, 107, 122, 127, 175, 191, 203, 215, 226, 245, 255, 351, 383, 407, 431, 442, 453, 491, 511, 530, 677, 703, 767, 815, 863, 885, 907, 962, 983, 1023, 1061, 1355, 1407, 1535, 1631, 1727, 1771, 1815, 1850, 1925, 1967, 2047, 2123, 2210, 2501
OFFSET
1,2
COMMENTS
See A191203.
LINKS
EXAMPLE
1 -> 2,3 -> 5,7,10 ->
MATHEMATICA
g = 11; Union[Flatten[NestList[{1 + 2 #, 1 + #^2} &, 1, g]]]
(* A191211; use g>10 to get all of first 60 terms *)
PROG
(Haskell)
import Data.Set (singleton, deleteFindMin, insert)
a191211 n = a191211_list !! (n-1)
a191211_list = f $ singleton 1 where
f s = m : f (insert (2 * m + 1) $ insert (m ^ 2 + 1) s')
where (m, s') = deleteFindMin s
-- Reinhard Zumkeller, Apr 18 2014
CROSSREFS
Cf. A191203.
Sequence in context: A266679 A285257 A317407 * A263133 A346592 A254860
KEYWORD
nonn
AUTHOR
Clark Kimberling, May 29 2011
STATUS
approved