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A036883
Number of partitions of 5n such that cn(0,5) <= cn(1,5) = cn(4,5) < cn(2,5) = cn(3,5).
5
1, 3, 7, 18, 45, 112, 263, 594, 1284, 2684, 5442, 10761, 20802, 39431, 73410, 134469, 242633, 431772, 758448, 1316294, 2258665, 3834699, 6445463, 10731790, 17709476, 28977664, 47036030, 75767355, 121164398, 192422933, 303572061, 475900075
OFFSET
1,2
COMMENTS
Alternatively, number of partitions of 5n such that cn(0,5) <= cn(2,5) = cn(3,5) < cn(1,5) = cn(4,5).
For a given partition, cn(i,n) means the number of its parts equal to i modulo n.
FORMULA
a(n) = A036880(n) - A202087(n)
a(n) = A036886(n) + A036893(n)
CROSSREFS
Sequence in context: A000226 A291734 A291229 * A247296 A191652 A191826
KEYWORD
nonn
EXTENSIONS
Terms a(10) onward from Max Alekseyev, Dec 10 2011
STATUS
approved