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 A280247 Partial sums of A280246 (Product_{d|n} psi(d)). 2
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS psi(n) is the sum of totatives of n (A023896). LINKS FORMULA a(n) = Sum_{i=1..n} A280246(i). MATHEMATICA Accumulate@ Table[Product[Total@ Select[Range@ d, CoprimeQ[d, #] &], {d, Divisors@ n}], {n, 37}] (* Michael De Vlieger, Dec 30 2016 *) PROG (MAGMA) [&+[&*[&+[h: h in [1..d] | GCD(h, d) eq 1]: d in Divisors(k)]: k in [1..n]]: n in [1..100]] CROSSREFS Cf. A023896, A280246, A280248. Sequence in context: A089089 A014495 A056326 * A261049 A122893 A178841 Adjacent sequences:  A280244 A280245 A280246 * A280248 A280249 A280250 KEYWORD nonn AUTHOR Jaroslav Krizek, Dec 30 2016 STATUS approved

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Last modified February 20 16:42 EST 2020. Contains 332080 sequences. (Running on oeis4.)