Number of ordered subsequences of {1,...,2n} containing at least n elements and such that the first differences contain only odd numbers.

A340766

Number of ordered subsequences of {1,...,2n} containing at least n elements and such that the first differences contain only odd numbers.

Terms

    a(0) =1a(1) =3a(2) =7a(3) =17a(4) =43a(5) =106a(6) =273a(7) =678a(8) =1759a(9) =4389a(10) =11430a(11) =28614a(12) =74685a(13) =187433a(14) =489926a(15) =1231957a(16) =3223387a(17) =8118434a(18) =21256897a(19) =53609282a(20) =140442534a(21) =354595210a(22) =929326086a(23) =2348710733a(24) =6157476873a(25) =15575365846a(26) =40843347873a(27) =103392210473a(28) =271181242774a(29) =686944588009

External references