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Old 2008-10-26, 03:23   #2
Jens K Andersen
 
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Feb 2006
Denmark

2·5·23 Posts
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I guess your program has a bug but I cannot say where without seeing the source. Here is a primitive PARI/GP search:
? for(p=1000000,1000100,if(isprime(p),for(d=1,9,q=10*p+d;if(isprime(q),for(e=1,9,r=10*q+e;if(isprime(r),for(f=11,99,s=100*r+f;if(isprime(s),print(s)))))))))
10000813327
10000813331
10000813351
10000813369
10000819937
10000819943
10000819963
10000993337
10000993351
10000993361
10000993399

If it's modified to only test numbers ending in 11 then it gives your list of numbers:
? for(p=1000000,1004000,if(isprime(p),for(d=1,9,q=10*p+d;if(isprime(q),for(e=1,9,r=10*q+e;if(isprime(r),for(f=11,11,s=100*r+f;if(isprime(s),print(s)))))))))
10006973311
10009319911
10010279911
10013897911
10014113311
10022599711
10026239911
10034639911
10039633711
10039637911
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