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A098227
Number of primes with exactly n decimal digits which have repeated digits.
Above n=9 a[n]=A006879[n] because above 10 repetition must occur. At n=10 the sum of digits 0+1+2+3+4+5+6+7+8+9=45 is divisible by 3, so no primes with 10 distinct decimal digits exists, all primes must have repeated digits.
Above n=9 a[n]=A006879[n] because above 10 there must be a repetition. At n=10 the sum of digits 0+1+2+3+4+5+6+7+8+9=45 is divisible by 3, so no primes with 10 distinct decimal digits exist.