A048973 Complement of A005243.

4, 7, 9, 12, 13, 15, 20, 23, 26, 27, 28, 31, 36, 38, 39, 42, 44, 48, 50, 52, 53, 55, 56, 61, 63, 64, 66, 74, 79, 83, 85, 89, 98, 101, 103, 107, 109, 114, 120, 123, 125, 128, 131, 133, 136, 144, 152, 157, 159, 160, 165, 168, 182, 184, 190, 192, 198, 203, 208, 212

Offset: 1

Author

D. R. Hofstadter

Keywords

• nonn
• easy
• nice

Comments

The sequence appears to be growing slightly faster than quadratically. - T. D. Noe, Nov 04 2007

Links

• T. D. Noe, Table of n, a(n) for n=1..6564 (terms < 10^8)

Programs

Haskell

import Data.List.Ordered (minus)
a048973 n = a048973_list !! (n-1)
a048973_list = [1..] `minus` a005243_list
-- Reinhard Zumkeller, Dec 17 2015

Mathematica

nmax = 250; For[ s = {1, 2}; n = 3, n <= nmax, n++, ls = Length[s]; tt = Total /@ Flatten[Table[s[[i ;; j]], {i, 1, ls - 1}, {j, i + 1, ls}], 1]; If[MemberQ[tt, n], AppendTo[s, n]]]; A048973 = Complement[Range[nmax], s] (* Jean-François Alcover, Oct 21 2016 *)

Extensions

More terms from Larry Reeves (larryr(AT)acm.org), Oct 02 2000