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A281024
Partial products of A067392; a(1) = 1.
1
1, 2, 6, 36, 180, 2700, 18900, 378000, 6804000, 238140000, 2619540000, 141455160000, 1838917080000, 115851776040000, 6951106562400000, 500479672492800000, 8508154432377600000, 995454068588179200000, 18913627303175404800000, 2458771549412802624000000
OFFSET
1,2
FORMULA
a(1) = 1; for n>1, a(n) = Product_{i=2..n} A067392(i).
PROG
(Magma) [1] cat [&*[&+[h: h in [2..k] | GCD(h, k) ne 1]: k in [2..n]]: n in [2..100]]
CROSSREFS
Cf. A067392(n) = sum of cototatives of n.
Cf. A281023.
Sequence in context: A323945 A369080 A101609 * A152668 A213918 A239889
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Jan 14 2017
STATUS
approved