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A085976
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Number of 2's in decimal expansion of prime(n).
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11
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1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0
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OFFSET
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1,48
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LINKS
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EXAMPLE
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prime(4) = 7, so a(4)=0 and prime(2490) = 22229, so a(2490)=4.
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MATHEMATICA
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DigitCount[Prime[Range[110]], 10, 2] (* Harvey P. Dale, Jan 14 2014 *)
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PROG
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(Haskell)
a085976 = count2 0 . a000040 where
count2 c x | d == 2 = if x < 10 then c + 1 else count2 (c + 1) x'
| otherwise = if x < 10 then c else count2 c x'
where (x', d) = divMod x 10
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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STATUS
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approved
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