Number of permutations of length n avoiding the pattern 1342 and with 1 appearing before n.
A248426
Number of permutations of length n avoiding the pattern 1342 and with 1 appearing before n.
Terms
- a(0) =1a(1) =3a(2) =11a(3) =46a(4) =211a(5) =1038a(6) =5400a(7) =29425a(8) =166767a(9) =977637a(10) =5901299a(11) =36538483a(12) =231286924a(13) =1492482109a(14) =9793849702a(15) =65217085321a(16) =439887071563
External references
- oeis: A248426