Odd k such that b(k) is less than b(k-1) and b(k+1). b(k): A033178.

Terms

a(0) =87a(1) =99a(2) =135a(3) =159a(4) =195a(5) =207a(6) =227a(7) =231a(8) =279a(9) =315a(10) =335a(11) =339a(12) =399a(13) =405a(14) =427a(15) =507a(16) =539a(17) =549a(18) =567a(19) =619a(20) =627a(21) =639a(22) =675a(23) =699a(24) =747a(25) =759a(26) =819a(27) =843a(28) =867a(29) =879