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%I #10 Aug 07 2019 05:32:10
%S 1,5,9,13,10,14,18,22,19,16,20,24,21,18,22,19,23,20,17,14,11,8,5,2,6,
%T 10,14,18,22,26,30,34,38,35,32,36,40,37,41,38,35,39,43,47,51,55,52,56,
%U 60,64,61,58,62,66,63,60,64,61,65,62,59,56,53,50,47,44,48,52,56,60,64,68
%N a(1) = 1; a(n) = a(n-1)-3 if n is already in the sequence, a(n) = a(n-1)+4 otherwise.
%F a(n) = n+b(n)-22 where b(n) is the 42-periodic sequence (22, 25, 28, 31, 27, 30, 33, 36, 32, 28, 31, 34, 30, 26, 29, 25, 28, 24, 20, 16, 12, 8, 4, 0, 3, 6, 9, 12, 15, 18, 21, 24, 27, 23, 19, 22, 25, 21, 24, 20, 16, 19)
%Y Cf. A079357.
%K nonn,hear
%O 1,2
%A _Benoit Cloitre_, Feb 14 2003