[seqfan] Re: Number of primes having distinct first and last digits both 7 to 10^n primes

Richard Mathar mathar at strw.leidenuniv.nl
Mon Aug 2 23:31:29 CEST 2010


i) One would like to have
A145713(n) = A145709(n)+ A145710(n)+A145711(n)+A145712(n) 

But A145713(n) = 150036 (currently) is 158036 by the formula (?).

ii)  Offset in A145712 should also be 1.

A145711 is

Number of primes p in the range 9<p<= prime(10^n) that have most significant and least
significant decimal digit 7.




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