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%I #10 Feb 28 2021 09:53:32
%S 89,138140141,87889091,8890919293,141516182021,122123124125126128129,
%T 121122123124125126128129,707274757677788081,21222425262728303233,
%U 206207208209210212213214215216217,405406407408410411412413414415416417
%N Smallest prime which is a concatenation of n successive composite numbers.
%C a(3) contains three digit composite numbers as every concatenation of two digit numbers n,n+2 and n+3 is == 0 (mod 7).
%H G. L. Honaker, Jr. and Chris Caldwell, <a href="https://primes.utm.edu/curios/page.php?short=138140141">Prime Curios! 138140141</a>.
%H G. L. Honaker, Jr. and Chris Caldwell, <a href="https://primes.utm.edu/curios/page.php?short=87889091">Prime Curios! 87889091</a>.
%e a(2) = 89 is the concatenation of two successive composite numbers 8 and 9.
%e a(3) = 138140141 is the concatenation of 138,140 and 141.
%Y Cf. A002808.
%K base,nonn
%O 2,1
%A _Amarnath Murthy_, Sep 06 2003
%E More terms from _David Wasserman_, May 10 2005
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