a(n) = A188492(n+1) - A188495(n) - A002527(n).

Terms

a(0) =0a(1) =0a(2) =2a(3) =4a(4) =10a(5) =28a(6) =96a(7) =304a(8) =928a(9) =2784a(10) =8504a(11) =26124a(12) =80228a(13) =245544a(14) =751168a(15) =2299184a(16) =7040986a(17) =21561028a(18) =66015398a(19) =202114264a(20) =618817376a(21) =1894692160a(22) =5801169248a(23) =17761879056a(24) =54382725520a(25) =166507388264a(26) =509808051944