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A009299
If a, b in sequence, so is a*b+2.
4
2, 6, 14, 30, 38, 62, 78, 86, 126, 158, 174, 182, 198, 230, 254, 318, 350, 366, 374, 398, 422, 462, 470, 510, 518, 534, 638, 702, 734, 750, 758, 798, 846, 870, 902, 926, 942, 950, 1022, 1038, 1046, 1070, 1094, 1142, 1190, 1206, 1278, 1382, 1406, 1446, 1470, 1502
OFFSET
1,1
LINKS
PROG
(Haskell)
import Data.Set (singleton, deleteFindMin, insert)
a009299 n = a009299_list !! (n-1)
a009299_list = f [2] (singleton 2) where
f xs s = m : f xs' (foldl (flip insert) s' (map ((+ 2) . (* m)) xs'))
where xs' = m : xs
(m, s') = deleteFindMin s
-- Reinhard Zumkeller, Aug 15 2011
CROSSREFS
Sequence in context: A112511 A143702 A063452 * A330766 A072611 A284023
KEYWORD
nonn
STATUS
approved