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 A069619 a(1) = 7; a(2n) = smallest prime that is a right concatenation of a(2n-1) and a number with no insignificant zeros and a(2n+1) = smallest prime ending in ( the least significant digits) a(2n-1). Alternate left and right concatenation yielding primes. 2
 7, 71, 271, 2711, 52711, 5271121, 135271121, 1352711219, 271352711219, 27135271121911, 1227135271121911, 122713527112191161, 20122713527112191161, 20122713527112191161109, 2720122713527112191161109 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE a(4) = 2711 staring with a(3) =271 and a(5) = 52711 in a(4) = 2711. CROSSREFS Cf. A053582, A069605, A069606, A069607, A069608, A069609, A069610, A069611, A069613, A069614, A069615, A069616, A069617, A069618. Sequence in context: A142928 A201261 A069634 * A137443 A100465 A107601 Adjacent sequences:  A069616 A069617 A069618 * A069620 A069621 A069622 KEYWORD nonn,base AUTHOR Amarnath Murthy (amarnath_murthy(AT)yahoo.com), 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 17:25 EDT 2013. Contains 225422 sequences.