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%I #15 Oct 30 2016 13:42:58
%S 1,2,3,6,5,2,15,30,7,10,3,30,35,2,105,210,11,70,21,30,5,10,105,42,77,
%T 70,3,210,385,2,1155,2310,13,770,231,30,55,70,105,6,7,2,21,42,385,10,
%U 165,66,143,110,231,210,5,70,1155,66,1001,770,3,2310,5005,2,15015,30030,17,10010,3003,30,715,770,105,66,91,154,231,6,385,70,15,42,11,14,3,42,55,2
%N a(0)=1, a(1)=2, a(2n) = A003961(a(n)), a(2n+1) = lcm(a(n),a(n+1))/gcd(a(n),a(n+1)).
%C Each term is a squarefree number, A005117.
%H Antti Karttunen, <a href="/A277330/b277330.txt">Table of n, a(n) for n = 0..8191</a>
%F a(0) = 1, a(1) = 2, a(2n) = A003961(a(n)), a(2n+1) = lcm(a(n),a(n+1))/gcd(a(n),a(n+1)).
%F Other identities. For all n >= 0:
%F a(n) = A007913(A260443(n)).
%F a(n) = A019565(A264977(n)), A048675(a(n)) = A264977(n).
%F A055396(a(n)) = A277707(A260443(n)) = A001511(n).
%o (Scheme, with memoization-macro definec)
%o (definec (A277330 n) (cond ((<= n 1) (+ 1 n)) ((even? n) (A003961 (A277330 (/ n 2)))) (else (/ (lcm (A277330 (/ (- n 1) 2)) (A277330 (/ (+ n 1) 2))) (gcd (A277330 (/ (- n 1) 2)) (A277330 (/ (+ n 1) 2)))))))
%Y Cf. A001511, A003961, A005117, A007913, A019565, A048675, A055396, A260443, A264977, A277707.
%Y Cf. A023758 (positions where coincides with A260443).
%Y Cf. A277701, A277712, A277713 for the positions of 2's, 3's and 6's in this sequence, which are also the first three rows of array A277710.
%Y Cf. also A255483.
%K nonn
%O 0,2
%A _Antti Karttunen_, Oct 27 2016
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