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A286433
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Number of entries in the second last blocks of all set partitions of [n].
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2
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1, 6, 25, 98, 399, 1746, 8271, 42284, 231939, 1357128, 8427181, 55288860, 381798629, 2765917074, 20960284277, 165729739590, 1364153612299, 11665484410094, 103448316470723, 949739632313480, 9013431476894623, 88304011710168668, 891917738589610553
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OFFSET
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2,2
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LINKS
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EXAMPLE
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a(3) = 6 because the number of entries in the second last blocks of all set partitions of [3] (123, 12|3, 13|2, 1|23, 1|2|3) is 0+2+2+1+1 = 6.
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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