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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A176024 Numbers k such that the reverse concatenation of the first k integers (A000422(k)) is a prime.

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%I A176024 #37 Feb 16 2025 08:33:12
%S A176024 82,37765
%N A176024 Numbers k such that the reverse concatenation of the first k integers (A000422(k)) is a prime.
%C A176024 a(1) was pointed out by _Artur Jasinski_, Mar 30 2008 (see A000422).
%C A176024 a(2) was found by _Eric W. Weisstein_, Apr 06 2010.
%C A176024 a(3) > 84300. - _Tyler Busby_, Feb 21 2023
%H A176024 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/ConsecutiveNumberSequences.html">Consecutive Number Sequences</a>
%H A176024 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/IntegerSequencePrimes.html">Integer Sequence Primes</a>
%H A176024 <a href="/index/Mo#MWP">Index entries for sequences related to Most Wanted Primes video</a>
%e A176024 a(1) is 82 since the 155-digit number 828180...54321 is prime.
%e A176024 a(2) is 37765 since the 177719-digit number 377653776437763...54321 is (a probable) prime.
%Y A176024 Cf. A000422, A007908, A176942.
%K A176024 nonn,hard,more,base,bref
%O A176024 1,1
%A A176024 _Eric W. Weisstein_, Apr 06 2010
%E A176024 Edited by _N. J. A. Sloane_, Dec 03 2021