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A309171
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a(n) = Product_{d|n} Stirling2(n,d).
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1
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1, 1, 1, 7, 1, 2790, 1, 216027, 3025, 21730275, 1, 143362465643243568744, 1, 404056132480, 500592722458920, 12056706465173227408551, 1, 99260615209905051640711424376160950, 1, 105138504356810366747790360523498652392500, 143413971571112402506500, 768149712982621155186
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OFFSET
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1,4
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LINKS
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MATHEMATICA
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Table[Product[StirlingS2[n, d], {d, Divisors[n]}], {n, 1, 22}]
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PROG
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(PARI) a(n) = my(d=divisors(n)); prod(k=1, #d, stirling(n, d[k], 2)); \\ Michel Marcus, Jul 16 2019
(Magma) [(&*[StirlingSecond(n, d): d in Divisors(n)]): n in [1..30]]; // Vincenzo Librandi, Jul 16 2019
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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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