A280247 Partial sums of A280246 (Product_{d|n} psi(d)).

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

Offset: 1

Author

Jaroslav Krizek, Dec 30 2016

Keywords

• nonn

Comments

psi(n) is the sum of totatives of n (A023896).

Crossrefs

Cf. A023896, A280246, A280248.

Programs

Magma

[&+[&*[&+[h: h in [1..d] | GCD(h,d) eq 1]: d in Divisors(k)]: k in [1..n]]: n in [1..100]];

Mathematica

Accumulate@ Table[Product[Total@ Select[Range@ d, CoprimeQ[d, #] &], {d, Divisors@ n}], {n, 37}] (* Michael De Vlieger, Dec 30 2016 *)

Formula

a(n) = Sum_{i=1..n} A280246(i).