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 A194263 Numbers that occur more than once in A193873, in order of appearance. 1
 1729, 13981, 88537, 51319, 137149, 548497, 285541, 3372529, 18326641, 1152271, 1809641, 3828001, 4814857, 4797703, 79230049, 4413223, 4209661, 19703611, 3882139, 50357677, 70611161, 26536591, 175493677, 85409941, 12932989, 84350561, 192754871 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Note that a(1) = 1729 is known as the Hardy-Ramanujan number (see A001235). Apparently these numbers occur only twice in A193873. LINKS FORMULA It appears that a(n) = A193873(2*n+1). EXAMPLE 1729 is in the sequence because the Hardy-Ramanujan number is also the smallest product of three distinct primes of the form 3*k+1 and also of the form 6*k+1, so 1729 occurs more than once in A193873. CROSSREFS Cf. A001235, A154729, A193869, A193873. Sequence in context: A130859 A154716 A154728 * A212920 A182087 A033502 Adjacent sequences:  A194260 A194261 A194262 * A194264 A194265 A194266 KEYWORD nonn,more AUTHOR Omar E. Pol, Sep 02 2011 STATUS approved

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