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%I #25 Mar 12 2016 12:36:15
%S 3,37,89,157,163,173,211,239,257,263,269,277,337,359,379,439,479,521,
%T 541,547,607,659,673,683,733,947,977,1019,1039,1187,1193,1213,1229,
%U 1277,1373,1459,1471,1663,1693,1721,1747,1867,1979,2081,2179
%N Previous prime concatenated with this prime p is a prime.
%C Terms 157, 257, 263, 541, 1187, 1459, 2179 also belong to A030459. [_Carmine Suriano_, Jan 27 2011]
%H Harvey P. Dale, <a href="/A030460/b030460.txt">Table of n, a(n) for n = 1..10000</a> [extending M.F. Hasler's prior b-File beyond n=4110]
%F A030459(n) = A151799(a(n)). - _M. F. Hasler_, Feb 06 2011
%F A030461(n) = concat(A030459(n),a(n)) = A045533( A000720( A030459(n))). - _M. F. Hasler_, Feb 06 2011
%t Transpose[Select[Partition[Prime[Range[400]],2,1], PrimeQ[FromDigits[ Flatten[IntegerDigits/@#]]]&]][[2]] (* _Harvey P. Dale_, Dec 23 2011 *)
%o (PARI) c=0; o=2; s=1; forprime(p=3,default(primelimit), p>s & s*=10; isprime(o*s+o=p) & write("b030460.txt",c++," ",p)) \\ _M. F. Hasler_, Feb 06 2011
%K nonn,base
%O 1,1
%A _Patrick De Geest_
%E Offset changed from 0 to 1 by _M. F. Hasler_, Feb 06 2011
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