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A179872
Numbers h such that antiharmonic mean B(h) of the numbers k < h such that gcd(k, h) = 1 is not integer.
17
3, 4, 6, 7, 8, 9, 12, 13, 14, 15, 16, 18, 19, 20, 21, 24, 25, 26, 27, 28, 30, 31, 32, 33, 35, 36, 37, 38, 39, 40, 42, 43, 44, 45, 48, 49, 50, 51, 52, 54, 56, 57, 60, 61, 62, 63, 64, 65, 66, 67
OFFSET
1,1
COMMENTS
Numbers h such that B(h) = A053818(h) / A023896(h) = A175505(h) / A175506(h) is not integer. Numbers h such that A175506(h) > 1. Complement of A179871. a(n) = union A007645 and A179891.
EXAMPLE
a(6) = 9 because B(9) = A053818(9) / A023896(9) = 159/27 = 53/9 (not integer).
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Jul 30 2010, Jul 31 2010
STATUS
approved