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Primes from products of split even-digit primes.
3

%I #16 Dec 03 2021 10:42:02

%S 3,7,3,7,103,109,103,409,601,109,709,907,523,139,193,853,379,397,739,

%T 937,499,223,499,1621,2161,6121,6211,4261,4621,6421,2017,2551,5521,

%U 139,193,769,967,997,109,3001,1039,1093,3019,3109,9013,9103,4111,1153,1531

%N Primes from products of split even-digit primes.

%D C. A. Pickover, chapter 30 of Keys to Infinity. NY: Wiley, 1995. Pages 227-231.

%H Sean A. Irvine, <a href="https://github.com/archmageirvine/joeis/blob/master/src/irvine/oeis/a053/A053008.java">Java program</a> (github)

%F Take even-digit primes, split digits into two halves, multiply the halves and form primes by rearranging digits. If split in right half results in a leading zero, that prime is skipped.

%F If more than one prime can be formed from the digits of the product, then each appears in numerical order. Consequently this sequence is not in one-to-one correspondence with the terms of A053009 and A053010. - _Sean A. Irvine_, Dec 02 2021

%e 103 is a term because from the prime 1013 we get 10 and 13 after the split; 10*13=130 and the digits 1 3 0 can be arranged to form 103, prime.

%Y Cf. A053009, A053010.

%K easy,nonn,base

%O 1,1

%A _Enoch Haga_, Feb 21 2000

%E Missing terms inserted by _Sean A. Irvine_, Dec 02 2021