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A119293
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Total number of 2's digits in the first 10^n primes.
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7
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3, 26, 339, 4070, 55213, 632418, 7133747, 82051293, 1041785731, 12182327373, 137771632675, 1525041000685
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OFFSET
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1,1
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COMMENTS
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Count the 2's digits in 10^n primes.
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LINKS
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EXAMPLE
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At a(1)=3 there are 3 2's digits in the first 10^1 primes.
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MAPLE
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A119293 := proc(n) option remember: local k, s, lim: if(n=0)then return 1:fi: lim:=10^n: s:=procname(n-1): for k from 10^(n-1)+1 to lim do s:=s+nops([SearchAll("2", convert(ithprime(k), string))]): od: return s: end: seq(A119293(n), n=1..4); # Nathaniel Johnston, May 09 2011
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MATHEMATICA
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Table[Count[IntegerDigits[Prime[Range[10^n]]], 2, 2], {n, 6}] (* Robert Price, May 02 2019 *)
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CROSSREFS
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KEYWORD
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more,nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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