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A095814
Number of nonisomorphic partitions of n on the Ferrers diagram.
0
1, 1, 1, 2, 3, 4, 6, 8, 11, 15, 21, 28, 39, 51, 68, 88, 116, 149, 193, 245, 314, 396, 501, 628, 788, 979, 1218, 1505, 1859, 2283, 2802, 3421, 4175, 5072, 6155, 7442, 8989, 10819, 13008, 15593, 18669, 22292, 26587, 31631, 37588, 44567, 52779, 62377
OFFSET
0,4
COMMENTS
Partitions of n into at most ceiling(n/2) parts and with at least 1 part greater than or equal to n - floor(n/2).
FORMULA
a(n) = A000041(n)/2 if A000041(n) is even and (A000041(n)+1)/2 if A000041(n) is odd.
EXAMPLE
a(5) = 4 because the 4 nonisomorphic partitions of 5 are (5), (4,1), (3,2), (3,1,1).
PROG
(PARI)
CROSSREFS
Sequence in context: A046935 A241334 A374760 * A006683 A014213 A341218
KEYWORD
nonn
AUTHOR
Jon Perry, Jul 13 2004
STATUS
approved