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A179890
Values of antiharmonic mean B(q) of the numbers k < q such that gcd(k, q) = 1 is integer for nonprimes q from A179887, where B(q) = A053818(q) / A023896(q) = A175505(q) / A175506(q).
20
1, 7, 15, 23, 31, 37, 39, 55, 57, 61, 63, 71, 73, 77, 79, 89, 95, 97, 111, 113, 119, 121, 125, 135, 137, 143, 145, 151, 153, 157, 165, 169, 173, 175, 177, 177, 183
OFFSET
1,2
FORMULA
a(n) = A175505(A003627(n)).
EXAMPLE
a(6) = 37 because for A179887(6) = 55 holds: B(55) = A053818(55)/A023896(55) = 40700/1100 = 37.
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Jul 30 2010, Jul 31 2010
STATUS
approved