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A091033
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Third column (k=4) of array A090438 ((4,2)-Stirling2).
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2
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1, 180, 25200, 4233600, 898128000, 239740300800, 79332244992000, 32011868528640000, 15509750302126080000, 8898339094906060800000, 5971815866682429603840000, 4637851802955964809216000000
(list; graph; refs; listen; history; internal format)
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OFFSET
| 2,2
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FORMULA
| a(n)=A090438(n, 4), n>=2.
a(n)= (n-1)*(2*n-3)*(2*n)!/4! = binomial(2*(n-1), 2)*(2*n)!/4! = A000384(n-1)*(2*n)!/4!, n>=2.
E.g.f.: (6*hypergeom([1/2, 1], [], 4*x) - 4*hypergeom([1, 3/2], [], 4*x) + hypergeom([3/2, 2], [], 4*x) -3)/4! (cf. A090438).
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CROSSREFS
| Cf. A091032 (second column of A090438 divided by 8), A091034 (fourth column divided by 24).
Sequence in context: A008432 A008378 A035830 * A146530 A057867 A075871
Adjacent sequences: A091030 A091031 A091032 * A091034 A091035 A091036
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KEYWORD
| nonn,easy
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AUTHOR
| Wolfdieter Lang (wolfdieter.lang_AT_physik_DOT_uni-karlsruhe_DOT_de), Jan 23 2004
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