Triangle read by rows: number of permutations of length n that require exactly k removals from the beginning to become heapable.
A390368
Triangle read by rows: number of permutations of length n that require exactly k removals from the beginning to become heapable.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =2a(4) =2a(5) =2a(6) =5a(7) =6a(8) =6a(9) =7a(10) =17a(11) =20a(12) =24a(13) =27a(14) =32a(15) =71a(16) =85a(17) =100a(18) =132a(19) =151a(20) =181a(21) =359a(22) =426a(23) =510a(24) =650a(25) =872a(26) =1009a(27) =1214a(28) =2126a(29) =2513
External references
- oeis: A390368