Number of peaks in all bargraphs having semiperimeter n (n>=2).

Terms

a(0) =1a(1) =2a(2) =5a(3) =13a(4) =36a(5) =105a(6) =317a(7) =979a(8) =3070a(9) =9731a(10) =31090a(11) =99940a(12) =322832a(13) =1047007a(14) =3407017a(15) =11118165a(16) =36370984a(17) =119234791a(18) =391620238a(19) =1288394790a(20) =4244993865a(21) =14005026856a(22) =46260856498a(23) =152974164616a(24) =506355410344