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%I #36 Oct 19 2023 23:18:37
%S 7,7,7,853,1286220583,178706126107,888895528231807,16197229696176289
%N a(n) is the smallest prime in a sequence of 2n consecutive primes that form a symmetrical constellation of cousin primes.
%C A cousin prime pair is a pair of primes that differ by 4.
%C a(8) was found by the T. Brada Experimental Grid BOINC project.
%H N. Makarova and C. Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_841.htm">Puzzle 841. Symmetrical compositions of consecutive pairs of cousin primes</a>, The Prime Puzzles and Problems Connection.
%e a(2) = 7 since the 4 consecutive primes (7, 11, 13, 17) are two pairs of cousin primes which are symmetrical because 7 + 17 = 11 + 13.
%Y Cf. A274792.
%K nonn,more
%O 1,1
%A _Natalia Makarova_, Mar 30 2022
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