Numbers k for which exactly 5 applications of A000005 are needed to reach 2.

Terms

a(0) =60a(1) =72a(2) =84a(3) =90a(4) =96a(5) =108a(6) =126a(7) =132a(8) =140a(9) =150a(10) =156a(11) =160a(12) =180a(13) =198a(14) =200a(15) =204a(16) =220a(17) =224a(18) =228a(19) =234a(20) =240a(21) =252a(22) =260a(23) =276a(24) =288a(25) =294a(26) =300a(27) =306a(28) =308a(29) =315