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%I #7 Aug 28 2017 01:02:13
%S 1,2,4,4,13,18,40,71,132,231,459,990,2114,4237,8234,16054,31280,60252,
%T 115810
%N a(n) = A289676(3*n+2).
%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