Number of permutations p of [n] such that |p(i) - p(i-1)| <= |p(i+1) - p(i)|.

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =6a(5) =8a(6) =10a(7) =14a(8) =20a(9) =24a(10) =32a(11) =40a(12) =48a(13) =70a(14) =94a(15) =126a(16) =162a(17) =228a(18) =292a(19) =386a(20) =528a(21) =710a(22) =956a(23) =1298a(24) =1730a(25) =2342a(26) =3178a(27) =4192a(28) =5684a(29) =7720