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%I #7 Aug 28 2017 01:02:37
%S 0,2,4,11,22,43,85,171,366,774,1586,3136,6123,12088,24283,49040,99031,
%T 200444,405931
%N a(n) = A289677(3*n+1).
%C No formulas or recurrences are known for the important sequences A289670 and A289671. The essence of these two sequences is captured in the six entries A290436-A290441. Any numerical properties of these would be most welcome.
%Y Cf. A284116, A284119, A284121, A289670-A289677, A290436-A290441.
%K nonn,more
%O 0,2
%A _N. J. A. Sloane_, Aug 02 2017