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 A224848 Reverse concatenation of the square of first a(n) integers gives a prime. 0
 2, 3, 14, 700, 2818 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The number corresponding to a(5) = 2818 is a probable prime of 18269 digits. - Giovanni Resta, Jul 25 2013 The number corresponding to a(5) = 2818 is prime (definite, not probable), according to Wolfram Mathematica 11.0 and Maple 2018. - Kellen Myers, Dec 04 2019 LINKS EXAMPLE a(4) = 700 because reverse concatenation of squares of 1 to 700 gives 490000488601......2516941 which is a 3742-digit prime number. CROSSREFS Cf. A091314. Sequence in context: A101003 A042071 A042817 * A271330 A262462 A180698 Adjacent sequences:  A224845 A224846 A224847 * A224849 A224850 A224851 KEYWORD nonn,hard,more,base AUTHOR Shyam Sunder Gupta, Jul 22 2013 EXTENSIONS a(5) from Giovanni Resta, Jul 25 2013 STATUS approved

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Last modified September 27 12:30 EDT 2020. Contains 337380 sequences. (Running on oeis4.)