Positive integers m for which f(m-1) < f(m) < f(m+1), where f(m) = floor(cot(Pi/(2m))).

Terms

a(0) =4a(1) =7a(2) =12a(3) =15a(4) =18a(5) =23a(6) =26a(7) =29a(8) =34a(9) =37a(10) =40a(11) =45a(12) =48a(13) =51a(14) =54a(15) =59a(16) =62a(17) =65a(18) =70a(19) =73a(20) =76a(21) =81a(22) =84a(23) =87a(24) =92a(25) =95a(26) =98a(27) =103a(28) =106a(29) =109