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A174904 Smallest number m such that A174903(m) = n. 2
1, 6, 18, 12, 105, 24, 36, 48, 495, 60, 400, 192, 144, 120, 4656, 180, 1600, 240, 576, 1120, 10000, 360, 1296, 2240, 900, 960, 28920, 720, 25600, 840, 9216, 5600, 5184, 1260, 102400, 6160, 36864, 1680, 302500, 2880, 19600, 15360, 3600, 12320 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
A174903(a(n)) = n and A174903(m) <> n for m < a(n).
LINKS
EXAMPLE
a(2)=18, A174903(18)=#{(2,3),(6,9)}=2;
a(3)=12, A174903(12)=#{(2,3),(3,4),(4,6)}=3;
a(4)=105, A174903(105)=#{(3,5),(5,7),(15,21),(21,35)}=4;
a(5)=24, A174903(24)=#{(2,3),(3,4),(4,6),(6,8),(8,12)}=5.
PROG
(Haskell)
import Data.List (elemIndex); import Data.Maybe (fromJust)
a174904 = (+ 1) . fromJust . (`elemIndex` map a174903 [1..])
-- Reinhard Zumkeller, Sep 29 2014
CROSSREFS
Sequence in context: A091014 A097370 A252897 * A074390 A255617 A253771
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Apr 01 2010
STATUS
approved

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Last modified April 24 20:08 EDT 2024. Contains 371963 sequences. (Running on oeis4.)