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A307507
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Brazilian semiprimes.
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1
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10, 14, 15, 21, 22, 26, 33, 34, 35, 38, 39, 46, 51, 55, 57, 58, 62, 65, 69, 74, 77, 82, 85, 86, 87, 91, 93, 94, 95, 106, 111, 115, 118, 119, 121, 122, 123, 129, 133, 134, 141, 142, 143, 145, 146, 155, 158, 159, 161, 166, 177, 178, 183, 185, 187, 194, 201, 202, 203, 205, 206, 209, 213, 214, 215, 217, 218
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OFFSET
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1,1
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COMMENTS
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Comparison with A001358 (semiprimes): in this sequence, there are no squared primes apart from 121 = (11111)_3, and also 6 is missing from here since it is not Brazilian.
Different from the squarefree semiprimes of A006881: this sequence = {A006881 \ 6} Union {121}.
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LINKS
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EXAMPLE
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a(20) = 74 = 2 * 37 = (22)_36 is semiprime and Brazilian.
25 = 5 * 5 is semiprime and no Brazilian, and 45 = (55)_8 = (33)_14 = 3^2 * 5 is Brazilian but no semiprime.
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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