A118030 a(1)=1. a(n) = a(n-1) + (largest integer which is <= n and occurs among the earlier terms of the sequence).

1, 2, 4, 8, 12, 16, 20, 28, 36, 44, 52, 64, 76, 88, 100, 116, 132, 148, 164, 184, 204, 224, 244, 264, 284, 304, 324, 352, 380, 408, 436, 464, 492, 520, 548, 584, 620, 656, 692, 728, 764, 800, 836, 880, 924, 968, 1012, 1056, 1100, 1144, 1188, 1240, 1292, 1344, 1396, 1448, 1500, 1552, 1604, 1656, 1708, 1760

Offset: 1

Author

Leroy Quet, Apr 10 2006

Keywords

• easy
• nonn

Links

• Michael De Vlieger, Table of n, a(n) for n = 1..5000

Crossrefs

Cf. A118026, A118027, A118028, A118029, A094589.

Programs

Mathematica

a = {1}; Do[k = i + 1; While[Nand[MemberQ[a, k], k <= i + 1], k--]; AppendTo[a, a[[i]] + k], {i, 61}]; a (* Michael De Vlieger, Sep 19 2017 *)

Extensions

More terms from Melissa Donovan (msd181(AT)psu.edu), Apr 23 2006