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A214626 a(n) = (a(n-1) + a(n-3)) / gcd(a(n-1), a(n-3)) with a(0) = a(1) = 1 and a(2) = 3. 4

%I

%S 1,1,3,4,5,8,3,8,2,5,13,15,4,17,32,9,26,29,38,32,61,99,131,192,97,228,

%T 35,132,30,13,145,35,48,193,228,23,216,37,60,23,60,2,25,17,19,44,61,

%U 80,31,92,43,74,83,126,100,183,103,203,386,489,692,539,1028

%N a(n) = (a(n-1) + a(n-3)) / gcd(a(n-1), a(n-3)) with a(0) = a(1) = 1 and a(2) = 3.

%C This sequence is to A179070 (without initial term) as A214551 is to A000930. - _Reinhard Zumkeller_, Jul 23 2012

%H Reinhard Zumkeller, <a href="/A214626/b214626.txt">Table of n, a(n) for n = 0..10000</a>

%t RecurrenceTable[{a[n] == (a[n - 1] + a[n - 3])/GCD[a[n - 1], a[n - 3]], a[0] == 1, a[1] == 1, a[2] == 3}, a , {n,0,100}] (* _G. C. Greubel_, Apr 27 2017 *)

%o (Haskell)

%o a214626 n = a214626_list !! n

%o a214626_list = 1 : 1 : 3 : zipWith f a214626_list (drop 2 a214626_list)

%o where f u v = (u + v) `div` gcd u v

%Y Cf. A214551, A179070, A000930, A214331, A214330, A214809.

%K nonn

%O 0,3

%A _Reinhard Zumkeller_, Jul 23 2012

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Last modified July 14 10:01 EDT 2020. Contains 335721 sequences. (Running on oeis4.)