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A211863
Number of partitions of n into parts <= 8 with the property that all parts have distinct multiplicities.
7
1, 1, 2, 2, 4, 5, 7, 10, 13, 14, 20, 26, 28, 40, 49, 53, 71, 89, 95, 125, 136, 160, 192, 235, 248, 313, 348, 409, 458, 558, 592, 729, 785, 921, 1018, 1205, 1264, 1511, 1627, 1888, 2037, 2382, 2521, 2961, 3143, 3660, 3884, 4502, 4782, 5510
OFFSET
0,3
EXAMPLE
For n=3 the a(3)=2 partitions are {3} and {1,1,1}. Note that {2,1} does not count, as 1 and 2 appear with the same nonzero multiplicity.
PROG
(Haskell)
a211863 n = p 0 [] [1..8] n where
p m ms _ 0 = if m `elem` ms then 0 else 1
p _ _ [] _ = 0
p m ms ks'@(k:ks) x
| x < k = 0
| m == 0 = p 1 ms ks' (x - k) + p 0 ms ks x
| m `elem` ms = p (m + 1) ms ks' (x - k)
| otherwise = p (m + 1) ms ks' (x - k) + p 0 (m : ms) ks x
-- Reinhard Zumkeller, Dec 27 2012
KEYWORD
nonn
AUTHOR
Matthew C. Russell, Apr 25 2012
STATUS
approved