editing
approved
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editing
approved
a(0), a(21)-a(37) from Alois P. Heinz, Nov 21 2019
1, 1, 1, 3, 6, 11, 14, 34, 52, 114, 225, 464, 539, 1183, 1963, 3753, 6120, 11207, 19808, 38254, 77194, 147906, 224853, 374216, 611081, 1099933, 2129347, 3336099, 5816094, 9797957, 17577710, 29766586, 53276392, 93139668, 163600815, 324464546, 637029845, 1010826499
1,3
0,4
nonn,more,new
approved
editing
proposed
approved
editing
proposed
allocated for Gus WisemanNumber of compositions of n whose multiplicities cover an initial interval of positive integers.
1, 1, 3, 6, 11, 14, 34, 52, 114, 225, 464, 539, 1183, 1963, 3753, 6120, 11207, 19808, 38254, 77194
1,3
A composition of n is a finite sequence of positive integers with sum n.
The a(1) = 1 through a(6) = 14 compositions:
(1) (2) (3) (4) (5) (6)
(1,2) (1,3) (1,4) (1,5)
(2,1) (3,1) (2,3) (2,4)
(1,1,2) (3,2) (4,2)
(1,2,1) (4,1) (5,1)
(2,1,1) (1,1,3) (1,1,4)
(1,2,2) (1,2,3)
(1,3,1) (1,3,2)
(2,1,2) (1,4,1)
(2,2,1) (2,1,3)
(3,1,1) (2,3,1)
(3,1,2)
(3,2,1)
(4,1,1)
normQ[m_]:=Or[m=={}, Union[m]==Range[Max[m]]];
Table[Length[Select[Join@@Permutations/@IntegerPartitions[n], normQ[Length/@Split[Sort[#]]]&]], {n, 20}]
allocated
nonn,more
Gus Wiseman, Nov 20 2019
approved
editing
allocated for Gus Wiseman
allocated
approved