A009299 If a, b in sequence, so is a*b+2.

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

Author

David W. Wilson

Keywords

• nonn

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A009293, A192476.

Programs

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