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A231590
Total number of 1's digits in primes less than 10^n.
10
0, 9, 78, 681, 6353, 59634, 570157, 5510645, 53680317, 525651276, 5166809159, 50931212973, 503152799893, 4979293536415
OFFSET
1,2
EXAMPLE
a(2)=9, since there are 9 1's in primes less than 100. Namely: 11, 13, 17, 19, 31, 41, 61, 71. Note that 11 counts for two.
MATHEMATICA
Table[Count[IntegerDigits[Prime[Range[PrimePi[10^n - 1]]]], 1, 2], {n, 7}] (* Robert Price, Jun 16 2019 *)
KEYWORD
nonn,base,more
AUTHOR
Robert Price, Nov 11 2013
EXTENSIONS
a(14) from Giovanni Resta, Jul 20 2015
STATUS
approved