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 A176024 Reverse concatenation of the first a(n) integers gives a prime. 1
 82, 37765 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(2) found by Eric W. Weisstein, Apr 06 2010. a(n) = indices n for which A000422(n) is prime. - Arkadiusz Wesolowski, Apr 29 2012 LINKS Eric Weisstein's World of Mathematics, Consecutive Number Sequences Eric Weisstein's World of Mathematics, Integer Sequence Primes EXAMPLE a(1) is 82 since the 155-digit number 828180...54321 is prime. a(2) is 37765 since the 177719-digit number 377653776437763...54321 is prime. CROSSREFS Sequence in context: A241129 A289330 A282157 * A204976 A204703 A206648 Adjacent sequences:  A176021 A176022 A176023 * A176025 A176026 A176027 KEYWORD nonn,hard,more,base,bref AUTHOR Eric W. Weisstein, Apr 06 2010 STATUS approved

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Last modified December 5 09:47 EST 2020. Contains 338945 sequences. (Running on oeis4.)