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%I #12 Sep 26 2016 14:13:25
%S 37,711,1317,1923,3741,4347,6771,7983,97101,103107,109113,127131,
%T 163167,193197,223227,229233,277281,307311,313317,349353,379383,
%U 397401,439443,457461,463467,487491,499503,613617,643647,673677,739743,757761,769773
%N Concatenations of pairs of primes that differ by four.
%H Chris Caldwell, <a href="http://www.utm.edu/research/primes/lists/small/1000.txt">The First 1,000 Primes</a>.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/CousinPrimes.html">Cousin Primes.</a>
%H M. Wolf, <a href="http://www.ift.uni.wroc.pl/~mwolf/">On Twin and Cousin Primes.</a>
%F a(n) = A023200(n) concatenated with A023200(n)+4. - _Jonathan Vos Post_, Mar 19 2005
%e The primes 3 and 7 differ by four, so the first term is 37.
%t s = Select[ Prime[ Range[ 140]], PrimeQ[ # + 4] &]; FromDigits /@ Join @@@ IntegerDigits /@ Transpose[{s, s + 4}] (* _Robert G. Wilson v_, Mar 19 2005 *)
%t Join[{37},FromDigits[Flatten[IntegerDigits/@#]]&/@Select[Partition[ Prime[ Range[ 200]],2,1],#[[2]]-#[[1]]==4&]] (* _Harvey P. Dale_, Sep 26 2016 *)
%K nonn,base
%O 1,1
%A _Parthasarathy Nambi_, Mar 18 2005
%E More terms from _Robert G. Wilson v_, Mar 19 2005
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