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%I #20 Aug 25 2016 21:42:09
%S 1111211111,1111411111,3333133333,9999499999,
%T 1111111111112111111111111111,1111311331137311333311111111,
%U 1111411441142411444411111111,1111611661167611666611111111,1111811881185811888811111111,3333033003305033000033333333,3333133113312133111133333333
%N Triangle-congruent primes greater than 10 with a single digit at the center.
%C Subsequence of A050758.
%H G. L. Honaker, Jr. and C. Caldwell, <a href="https://primes.utm.edu/curios/page.php?number_id=7464">1111211111</a>
%e a(6) can be represented as follows:
%e ......1
%e .....1 1
%e ....1 3 1
%e ...1 3 3 1
%e ..1 3 7 3 1
%e .1 3 3 3 3 1
%e 1 1 1 1 1 1 1
%Y Cf. A050758.
%K nonn,base
%O 1,1
%A _Felix Fröhlich_, Aug 22 2015