Number of binary heaps on [n] that give a heap when the first element is removed.
A273754
Number of binary heaps on [n] that give a heap when the first element is removed.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =2a(4) =3a(5) =8a(6) =18a(7) =70a(8) =180a(9) =770a(10) =2610a(11) =14570a(12) =54720a(13) =330960a(14) =1562814a(15) =11946080a(16) =57126780a(17) =429542960a(18) =2465050968a(19) =22517159760
External references
- oeis: A273754