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 A218011 Numbers n for which n’ = x’*y’, where x>0, y>0, n = x + y and n’, x’, y’ are the arithmetic derivatives of n, x, y. 1
 5, 7, 13, 19, 31, 43, 48, 55, 61, 73, 74, 87, 103, 106, 109, 117, 139, 146, 151, 159, 160, 178, 181, 193, 199, 202, 208, 212, 225, 229, 236, 241, 252, 267, 268, 271, 283, 285, 298, 313, 349, 357, 362, 386, 403, 411, 421, 433, 455, 463, 496, 511, 519, 523, 535 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The greatest prime in a twin primes couple is in the sequence. In fact if the twin primes are a and b, with a 0 &] (* T. D. Noe, Oct 18 2012 *) CROSSREFS Cf. A003415, A211223, A211224, A211225, A212662, A212663, A212664. Sequence in context: A243457 A189441 A106986 * A242255 A006512 A074304 Adjacent sequences:  A218008 A218009 A218010 * A218012 A218013 A218014 KEYWORD nonn AUTHOR Paolo P. Lava, Oct 18 2012 STATUS approved

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Last modified April 14 07:59 EDT 2021. Contains 342946 sequences. (Running on oeis4.)