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A280248
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Partial products of A280246 (Product_{d|n} psi(d)).
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2
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1, 1, 3, 12, 120, 2160, 45360, 2903040, 235146240, 47029248000, 2586608640000, 4469659729920000, 348633458933760000, 307494710779576320000, 553490479403237376000000, 2267097003635660292096000000, 308325192494449799725056000000
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OFFSET
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1,3
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COMMENTS
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psi(n) is the sum of totatives of n (A023896).
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LINKS
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FORMULA
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a(n) = Product_{i=1..n} A280246(i).
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MATHEMATICA
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FoldList[#1 #2 &, Table[Product[Total@ Select[Range@ d, CoprimeQ[d, #] &], {d, Divisors@ n}], {n, 17}]] (* Michael De Vlieger, Dec 30 2016 *)
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PROG
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(Magma) [&*[&*[&+[h: h in [1..d] | GCD(h, d) eq 1]: d in Divisors(k)]: k in [1..n]]: n in [1..100]]
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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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