Number of compositions of n where differences between neighboring parts are in {-2,0,2}.

Terms

a(0) =1a(1) =1a(2) =2a(3) =2a(4) =5a(5) =5a(6) =10a(7) =10a(8) =21a(9) =22a(10) =42a(11) =47a(12) =87a(13) =103a(14) =179a(15) =224a(16) =380a(17) =491a(18) =802a(19) =1074a(20) =1721a(21) =2354a(22) =3696a(23) =5157a(24) =7995a(25) =11305a(26) =17328a(27) =24778a(28) =37680a(29) =54320