A081146 Inverse permutation to A081145.

1, 2, 5, 3, 8, 11, 4, 6, 14, 17, 20, 9, 23, 7, 26, 12, 29, 32, 35, 10, 15, 38, 40, 43, 18, 46, 13, 21, 49, 52, 55, 58, 24, 16, 61, 64, 27, 67, 70, 72, 19, 30, 75, 77, 33, 80, 22, 36, 83, 86, 89, 92, 95, 25, 39, 98, 101, 41, 104, 28, 44, 107, 110, 113, 116, 47, 119, 31, 122

Offset: 1

Author

Don Reble, Mar 08 2003

Keywords

• nonn

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
• Index entries for sequences that are permutations of the natural numbers

Crossrefs

Cf. A081145.

Programs

Haskell

import Data.List (elemIndex); import Data.Maybe (fromJust)
a081146 = (+ 1) . fromJust . (`elemIndex` a081145_list)
-- Reinhard Zumkeller, Jul 02 2015

Mathematica

f[s_] := Block[{d = Abs[Rest@s - Most@s], k = 1}, While[ MemberQ[d, Abs[k - Last@s]] || MemberQ[s, k], k++ ]; Append[s, k]]; t = Nest[f, {1}, 130]; Table[ Position[t, n], {n, 70}] // Flatten (* Robert G. Wilson v, Jun 09 2006 *)
f[s_] := Block[{k = 1, d = Abs[Most@s - Rest@s], l = Last@s}, While[MemberQ[s, k] || MemberQ[d, Abs[l - k]], k++ ]; Append[s, k]]; t = Nest[f, {1}, 125]; Table[Position[t, n], {n, 71}] // Flatten (* Robert G. Wilson v, Jun 13 2006 *)