%I
%S 2607,4007,4069,7597,12411,13583,23041,31113,32619,46187,48469,55777,
%T 61411,64387,71143,73837,84761,103559,123797,124043,126613,136509,
%U 142019,147449,183981,186889,200183,204219,214819,221101,224123,230977
%N Concatenation of n in base 2 up to base 10 and n in base 10 down to base 2 is prime, all numbers are interpreted as decimals.
%e a(1)=2607 prime onwards: 10100010111110120120220233404122002310413505735162607.
%e Case prime downwards is: 26073516505710413200234041222023310120120101000101111.
%Y Cf. A054256, A054257.
%K nonn,base
%O 0,1
%A _Patrick De Geest_, Feb 15 2000
