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A280247
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Partial sums of A280246 (Product_{d|n} psi(d)).
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2
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1, 2, 5, 9, 19, 37, 58, 122, 203, 403, 458, 2186, 2264, 3146, 4946, 9042, 9178, 35422, 35593, 99593, 107531, 113581, 113834, 2768042, 2770542, 2782710, 2802393, 3395097, 3395503, 29315503, 29315968, 30364544, 30418994, 30455986, 30544186, 574739770, 574740436
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OFFSET
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1,2
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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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MATHEMATICA
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Accumulate@ Table[Product[Total@ Select[Range@ d, CoprimeQ[d, #] &], {d, Divisors@ n}], {n, 37}] (* 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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