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 A069614 a(1) = 2; a(2n) = smallest prime starting (the most significant digits) with a(2n-1) (i.e., as a right concatenation of a(2n-1) and a number with no insignificant zeros); a(2n+1) = smallest prime ending in (the least significant digits) a(2n-1). Alternate left and right concatenation yielding primes. 16
 2, 23, 223, 2237, 32237, 3223729, 63223729, 632237297, 2632237297, 263223729721, 12263223729721, 1226322372972173, 171226322372972173, 17122632237297217381, 2117122632237297217381, 21171226322372972173813 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE a(4) = 2111 staring with a(3) = 211 and a(5) = 22111 ending in a(4) = 2111. CROSSREFS Cf. A053582, A069605, A069606, A069607, A069608, A069609, A069610, A069611, A069613. Sequence in context: A030456 A069837 A069629 * A036937 A083808 A252016 Adjacent sequences:  A069611 A069612 A069613 * A069615 A069616 A069617 KEYWORD nonn,base AUTHOR Amarnath Murthy, Mar 27 2002 EXTENSIONS More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Mar 30 2003 STATUS approved

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Last modified May 18 10:28 EDT 2022. Contains 353807 sequences. (Running on oeis4.)