Number of permutations avoiding the patterns {4231, 4321, 35142, 45312, 42513, 45132, 35412, 45213, 43512, 456123, 351624, 451623, 356124}; number of strong sorting class based on 4231.
A111280
Number of permutations avoiding the patterns {4231, 4321, 35142, 45312, 42513, 45132, 35412, 45213, 43512, 456123, 351624, 451623, 356124}; number of strong sorting class based on 4231.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =6a(4) =22a(5) =113a(6) =431a(7) =1584a(8) =5920a(9) =22214a(10) =83239a(11) =311777a(12) =1167902a(13) =4375090a(14) =16389450a(15) =61395989a(16) =229993639a(17) =861572476a(18) =3227511492a(19) =12090486122a(20) =45291815419a(21) =169666341761a(22) =635582108218
External references
- oeis: A111280