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A095258 a(n+1) = smallest divisor of (2 + sum of first n terms) but not occurring earlier; a(1) = 1. 8
1, 3, 2, 4, 6, 9, 27, 18, 8, 5, 17, 34, 68, 12, 24, 10, 25, 11, 13, 23, 7, 47, 94, 235, 15, 16, 32, 48, 51, 289, 578, 102, 36, 26, 73, 219, 30, 20, 14, 46, 50, 470, 60, 40, 146, 21, 49, 28, 113, 29, 19, 35, 42, 54, 64, 22, 77, 329, 84, 56, 292, 365, 65, 37, 131, 38, 33 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Conjecture: integer permutation with inverse A095259: a(A095259(n))=A095259(a(n))=n. - Comment revised: Reinhard Zumkeller, Dec 31 2014

A095260(n) = a(a(n)).

First fixed points: 1,4,54,416, ...

A253415(n) = smallest missing number within the first n terms. - Reinhard Zumkeller, Dec 31 2014

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..797

Index entries for sequences that are permutations of the natural numbers

PROG

(Haskell)

import Data.List (delete)

a095258 n = a095258_list !! (n-1)

a095258_list = 1 : f [2..] 1 where

   f xs z = g xs where

     g (y:ys) = if mod z' y > 0 then g ys else y : f (delete y xs) (z + y)

     z' = z + 2

-- Reinhard Zumkeller, Dec 31 2014

CROSSREFS

Cf. A253415.

Sequence in context: A116425 A019653 A240493 * A114745 A039915 A085346

Adjacent sequences:  A095255 A095256 A095257 * A095259 A095260 A095261

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, May 31 2004

STATUS

approved

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Last modified February 19 10:34 EST 2019. Contains 320310 sequences. (Running on oeis4.)