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Partial sums of A280258.
2

%I #17 Sep 08 2022 08:46:18

%S 1,3,6,11,36,45,766,876,3119,3334,3632135,3632532,482634133,482654160,

%T 483551083,485578218,20923275466219,20923275553553,6423296981281554,

%U 6423296990011493,6423344287548216,6423345541114343,1124007151123148794344,1124007151123185976991

%N Partial sums of A280258.

%F a(n) = Sum_{i=1..n} A280258(i) where A280258(n) = Sum_{d|n} pxi(d), where pxi(m) is the product of totatives of m (A001783).

%t Accumulate@ Table[Sum[Times @@ Select[Range@ d, CoprimeQ[#, d] &], {d, Divisors@ n}], {n, 24}] (* _Michael De Vlieger_, Jan 01 2017 *)

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

%Y Cf. A001783, A280258, A280260.

%K nonn

%O 1,2

%A _Jaroslav Krizek_, Jan 01 2017