a(1)=0; thereafter a(2k)=k+a(k), a(2k+1)=6k+4+a(6k+4).

Terms

a(0) =0a(1) =1a(2) =46a(3) =3a(4) =31a(5) =49a(6) =281a(7) =7a(8) =330a(9) =36a(10) =248a(11) =55a(12) =106a(13) =288a(14) =679a(15) =15a(16) =197a(17) =339a(18) =500a(19) =46a(20) =127a(21) =259a(22) =610a(23) =67a(24) =633a(25) =119a(26) =101413a(27) =302a(28) =413a(29) =694