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A289182
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Positions of odd semiprimes in A001358.
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13
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3, 6, 7, 9, 11, 13, 15, 17, 18, 19, 20, 23, 24, 26, 28, 30, 31, 32, 34, 36, 37, 39, 40, 42, 43, 44, 46, 48, 49, 51, 53, 54, 56, 57, 59, 60, 61, 63, 65, 66, 68, 69, 71, 72, 74, 75, 77, 78, 79, 80, 81, 83, 85, 86, 89, 90, 91, 92, 94, 95, 97, 98
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OFFSET
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1,1
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COMMENTS
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Complement to A115392.
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LINKS
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Table of n, a(n) for n=1..62.
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FORMULA
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a(n) ~ n. - Charles R Greathouse IV, Jul 02 2017
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MATHEMATICA
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sp=Select[Range[4, 1000], 2==PrimeOmega[#]&]; Flatten[Position[Mod[sp, 2], 1]]
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PROG
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(PARI) lista(nn) = vsp = select(x->(bigomega(x)==2), vector(nn, k, k)); select(x->(x%2), vsp, 1); \\ Michel Marcus, Jul 02 2017
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CROSSREFS
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Cf. A001358, A115392.
Sequence in context: A221264 A026415 A026406 * A188974 A047558 A160217
Adjacent sequences: A289179 A289180 A289181 * A289183 A289184 A289185
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KEYWORD
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nonn
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AUTHOR
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Zak Seidov, Jun 27 2017
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STATUS
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approved
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