One-half of number of permutations of [n] with exactly one run of adjacent symbols differing by 1.
A000239
One-half of number of permutations of [n] with exactly one run of adjacent symbols differing by 1.
Terms
- a(0) =1a(1) =1a(2) =3a(3) =8a(4) =28a(5) =143a(6) =933a(7) =7150a(8) =62310a(9) =607445a(10) =6545935a(11) =77232740a(12) =989893248a(13) =13692587323a(14) =203271723033
External references
- oeis: A000239