a(n) = A002527(n+1) - A002527(n) - A002526(n).

Terms

a(0) =0a(1) =0a(2) =2a(3) =6a(4) =18a(5) =46a(6) =146a(7) =460a(8) =1436a(9) =4352a(10) =13252a(11) =40532a(12) =124396a(13) =381140a(14) =1166708a(15) =3570684a(16) =10932274a(17) =33475170a(18) =102499334a(19) =313825690a(20) =960844358a(21) =2941873064a(22) =9007393480a(23) =27578681888a(24) =84439657768a(25) =258534813320a(26) =791574775192