a(n) = A001672(n) - A115239(n).

Terms

a(0) =0a(1) =0a(2) =3a(3) =10a(4) =33a(5) =104a(6) =328a(7) =1031a(8) =3241a(9) =10183a(10) =31991a(11) =100503a(12) =315740a(13) =991928a(14) =3116234a(15) =9789941a(16) =30756009a(17) =96622854a(18) =303549648a(19) =953629346a(20) =2995914948a(21) =9411944394a(22) =29568495367a(23) =92892167824a(24) =291829352014a(25) =916808948392