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 A094298 Numbers n such that n and its 10's complement are both semiprimes, i.e., n and 10^k - n where k is the number of digits of n, are semiprime. 0
 4, 6, 14, 15, 26, 35, 38, 49, 51, 62, 65, 74, 85, 86, 91, 94, 111, 121, 122, 129, 134, 158, 159, 169, 183, 185, 187, 201, 206, 209, 215, 219, 221, 237, 247, 254, 287, 301, 302, 303, 305, 319, 321, 326, 329, 365, 371, 377, 386, 403, 411, 417, 427, 446, 447, 458 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE 201 is a term because both 201 and 1000 - 201 = 799 are semiprimes. MATHEMATICA Select[Range[500], PrimeOmega[#]==PrimeOmega[10^IntegerLength[#]-#]==2&] (* Harvey P. Dale, Jan 17 2013 *) CROSSREFS Cf. A001358. Sequence in context: A310616 A310617 A305842 * A089226 A102029 A310618 Adjacent sequences:  A094295 A094296 A094297 * A094299 A094300 A094301 KEYWORD easy,nonn,base AUTHOR Jason Earls, Jun 02 2004 STATUS approved

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Last modified February 23 12:38 EST 2020. Contains 332159 sequences. (Running on oeis4.)