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A024741
a(n) = Sum_{i=1..floor((n+1)/4)} a(2*i-1) * a(n-2*i+1), with a(1)=2, a(2)=1, and a(3)=3.
1
2, 1, 3, 6, 12, 24, 66, 168, 408, 1014, 2820, 7656, 20370, 54096, 154416, 430710, 1182504, 3258816, 9377922, 26651328, 74941608, 210709446, 612566616, 1760983512, 5017273554, 14308403856, 41833393896, 121321861350, 349444725492, 1006135834560
OFFSET
1,1
CROSSREFS
Sequence in context: A104529 A095024 A049900 * A024961 A260666 A140644
KEYWORD
nonn
STATUS
approved