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A280260 Partial products of A280258. 2
1, 2, 6, 30, 750, 6750, 4866750, 535342500, 1200773227500, 258166243912500, 936833924075923912500, 371923067858141793262500, 178151744952881559857748513262500, 3567844996171358999271129475108087500, 3200082237501003827703259262202371164762500 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
A280258(n) = Sum_{d|n} pxi(d), where pxi(m) is the product of totatives of m (A001783).
LINKS
FORMULA
a(n) = Product_{i=1..n} A280258(i).
MATHEMATICA
FoldList[#1 #2 &, #] &@ Table[Sum[Times @@ Select[Range@ d, CoprimeQ[#, d] &], {d, Divisors@ n}], {n, 15}] (* Michael De Vlieger, Jan 01 2017 *)
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: A320830 A074777 A007280 * A102927 A227105 A127295
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Jan 01 2017
STATUS
approved

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Last modified April 24 22:17 EDT 2024. Contains 371964 sequences. (Running on oeis4.)