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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
Sequence in context: A369854 A014495 A056326 * A261049 A122893 A178841
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Dec 30 2016
STATUS
approved

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Last modified May 10 02:42 EDT 2024. Contains 372354 sequences. (Running on oeis4.)