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A242842
Number of compositions of n with difference 2 between the number of odd parts and the number of even parts, both counted without multiplicity.
2
2, 3, 6, 11, 20, 25, 41, 85, 148, 355, 751, 1701, 3756, 8255, 17513, 37038, 76349, 156618, 317591, 639142, 1279302, 2546711, 5057675, 10010975, 19788607, 39058684, 77055159, 151930328, 299600229, 590849561, 1165782514, 2301229945, 4545782370, 8985884632
OFFSET
4,1
LINKS
EXAMPLE
a(4) = 2: [1,3], [3,1].
a(5) = 3: [1,1,3], [1,3,1], [3,1,1].
a(6) = 6: [1,1,1,3], [1,1,3,1], [1,3,1,1], [3,1,1,1], [1,5], [5,1].
CROSSREFS
Column k=2 of A242626.
Sequence in context: A238644 A191629 A285553 * A327665 A131269 A358027
KEYWORD
nonn
AUTHOR
Alois P. Heinz, May 23 2014
STATUS
approved