A160516 Inverse permutation to A075075.

1, 2, 5, 3, 6, 4, 17, 8, 10, 7, 18, 9, 23, 20, 11, 13, 24, 15, 58, 12, 16, 19, 59, 14, 33, 22, 28, 21, 62, 26, 63, 31, 29, 25, 34, 36, 66, 57, 39, 32, 67, 35, 72, 30, 27, 60, 125, 37, 49, 44, 40, 38, 126, 47, 45, 42, 71, 61, 131, 56, 134, 64, 48, 52, 80, 46, 135, 41, 76, 43

Offset: 1

Author

Hagen von Eitzen, May 16 2009

Keywords

• nonn

Comments

This is a permutation of the positive integers (provided A075075 really is a permutation).

Examples

			A075075(7) = 10, therefore a(10) = 7.
A075055(17) = 7, therefore a(7) = 17.
		

Links

• H. v. Eitzen, Table of n, a(n) for n = 1..50000

Crossrefs

Cf. A185635 (fixed points).

Programs

Haskell

import Data.List (elemIndex)
import Data.Maybe (fromJust)
a160516 = (+ 1) . fromJust . (`elemIndex` a075075_list)
-- Reinhard Zumkeller, Dec 19 2012

Mathematica

f[s_List] := Block[{m = Numerator[s[[ -1]]/s[[ -2]]]}, k = m; While[MemberQ[s, k], k += m]; Append[s, k]]; s = Nest[f, {1, 2}, 200]; Table[ Position[s, n, 1, 1], {n, 70}] // Flatten (* Robert G. Wilson v, May 20 2009 *)

Formula

A075075(a(n)) = n.