[seqfan] Smallest emirp with emirp number of digits and emirp digital sum
Jonathan Post
jvospost3 at gmail.com
Thu Nov 19 04:19:48 CET 2009
Is 1000000004161 the smallest emirp (A006567) with emirp number of
digits and emirp digital sum?
It is prime, its reversal 1614000000001 is prime, it has a prime 13
digits, R(13) = 31 is prime, and the
sum of digits 1+6+1+4+0+0+0+0+0+0+0+0+1 = 13 is prime (and reversed is
again the prime 31).
Or did I miss a smaller example in my sloppy by-hand search?
For people who hate the word "emirp" this may be the worst seq yet
encountered .. this an the 2nd smallest, 3rd smallest, etc.
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