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%I #5 Oct 06 2019 18:27:44
%S 467,941,8834,9548,13012,22302,23592,26208,47538,58578,78910,86447,
%T 86925,116230,118040,123716,128055,213493,234146,238326,273057,285315,
%U 286422,389336,399261,457810,468764,481476,502590,525402,541102,570205
%N Cycle of 3 steps possible for 'concatenate a(n) and nextprime(a(n)) is a prime'.
%e a(n)=78910 -> nextprime(a(n)) is 78919 so '7891078919' is prime (=step 1); a(n2)=7891078919 -> nextprime(a(n2)) is 7891078931 so '78910789197891078931' is prime (=step 2); a(n3)=78910789197891078931 -> nextprime(a(n3)) is 78910789197891078949 so '7891078919789107893178910789197891078949' is prime (=step 3).
%Y See also A034591-A034596, A030459.
%K nonn,base
%O 0,1
%A _Patrick De Geest_, Oct 15 1998
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