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A198727
Number of partitions of n into distinct positive Loeschian numbers (cf. A003136).
3
1, 1, 0, 1, 2, 1, 0, 2, 2, 1, 2, 2, 3, 4, 3, 2, 6, 6, 1, 5, 9, 6, 5, 9, 9, 9, 11, 8, 13, 17, 11, 12, 22, 19, 13, 23, 25, 22, 26, 28, 30, 37, 34, 31, 47, 45, 35, 50, 61, 52, 56, 69, 68, 76, 74, 72, 95, 100, 82, 100, 130, 112, 113, 139, 144, 149, 154, 156, 183
OFFSET
0,5
LINKS
EXAMPLE
a(20) = #{19+1, 16+4, 16+3+1, 13+7, 13+4+3, 12+7+1, 12+4+3+1, 9+7+4, 9+7+3+1} = 9;
a(21) = #{21, 16+4+1, 13+7+1, 13+4+3+1, 12+9, 9+7+4+1} = 6;
a(22) = #{21+1, 19+3, 13+9, 12+9+1, 12+7+3} = 5.
PROG
(Haskell)
import Data.MemoCombinators (memo2, list, integral)
a198727 n = a198727_list !! n
a198727_list = f 0 [] $ tail a003136_list where
f u vs ws'@(w:ws) | u < w = (p' vs u) : f (u + 1) vs ws'
| otherwise = f u (vs ++ [w]) ws
p' = memo2 (list integral) integral p
p _ 0 = 1
p [] _ = 0
p (k:ks) m = if m < k then 0 else p' ks (m - k) + p' ks m
-- Reinhard Zumkeller, Nov 16 2015, Oct 30 2011
CROSSREFS
Sequence in context: A229893 A317683 A366371 * A294508 A035152 A035204
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Oct 30 2011
STATUS
approved