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A326507
Number of (binary) max-heaps on n elements from the set {0,1} containing exactly six 0's.
2
1, 1, 2, 5, 9, 16, 27, 44, 68, 114, 156, 236, 325, 500, 622, 900, 1143, 1659, 1954, 2731, 3277, 4564, 5185, 7040, 8114, 10948, 12124, 16058, 17977, 23640, 25692, 33304, 36493, 46965, 50322, 64017, 69025, 87208, 92423, 115652, 123168, 153142, 160908, 198440
OFFSET
6,3
LINKS
Eric Weisstein's World of Mathematics, Heap
Wikipedia, Binary heap
Index entries for linear recurrences with constant coefficients, signature (1, 2, -2, 3, -3, -8, 8, -2, 2, 12, -12, -2, 2, -8, 8, 3, -3, 2, -2, -1, 1).
MATHEMATICA
LinearRecurrence[{1, 2, -2, 3, -3, -8, 8, -2, 2, 12, -12, -2, 2, -8, 8, 3, -3, 2, -2, -1, 1}, {1, 1, 2, 5, 9, 16, 27, 44, 68, 114, 156, 236, 325, 500, 622, 900, 1143, 1659, 1954, 2731, 3277}, 50] (* Ray Chandler, Sep 25 2022 *)
CROSSREFS
Column k=6 of A309049.
Sequence in context: A225596 A211881 A056870 * A014739 A290464 A335768
KEYWORD
nonn,easy
AUTHOR
Alois P. Heinz, Jul 09 2019
STATUS
approved