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A280458 Partial products of A023896. 0

%I

%S 1,1,3,12,120,720,15120,241920,6531840,130636800,7185024000,

%T 172440576000,13450364928000,564915326976000,33894919618560000,

%U 2169274855587840000,295021380359946240000,15931154539437096960000,2724227426243743580160000,217938194099499486412800000

%N Partial products of A023896.

%C A023896(n) = the sum of totatives of n.

%C a(n) = n! for n = 1, 5 and 6.

%F a(n) = Sum_{i=1..n} A023896(i).

%t FoldList[#1 #2 &, Table[Ceiling[(n EulerPhi@ n)/2], {n, 20}]] (* _Michael De Vlieger_, Jan 03 2017 *)

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

%Y Cf. A023896, A213544 (partial sums of A023896).

%K nonn

%O 1,3

%A _Jaroslav Krizek_, Jan 03 2017

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Last modified September 24 06:13 EDT 2021. Contains 347623 sequences. (Running on oeis4.)