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A231595
Total number of 6's digits in primes less than 10^n.
0
0, 2, 33, 369, 3741, 38714, 395621, 4007705, 40484195, 408035120, 4105718243, 41266320918, 414416274953, 4159068898063
OFFSET
1,2
EXAMPLE
a(2)=2, since there are 2 6's in primes less than 100. Namely: 61, 67.
MATHEMATICA
Table[Count[IntegerDigits[Prime[Range[PrimePi[10^n - 1]]]], 6, 2], {n, 7}] (* Robert Price, Jun 16 2019 *)
KEYWORD
more,nonn,base
AUTHOR
Robert Price, Nov 11 2013
EXTENSIONS
a(14) from Giovanni Resta, Jul 20 2015
STATUS
approved