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Search: id:A091637
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| A091637 |
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Number of primes less than 10^n which do not contain the digit 3. |
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+0
11
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| 3, 16, 102, 668, 4715, 34813, 265015, 2067152, 16413535, 132200223, 1076692515, 8849480283
(list; graph; listen)
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OFFSET
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1,1
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FORMULA
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Number of primes less than 10^n after removing any primes with at least one digit 3.
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EXAMPLE
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a(2)=16 because there are 25 primes less than 10^2, 9 have at least one digit 3; 25-9 = 16.
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MATHEMATICA
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NextPrim[n_] := Block[{k = n + 1}, While[ !PrimeQ[k], k++ ]; k]; c = 0; p = 1; Do[ While[ p = NextPrim[p]; p < 10^n, If[ Position[ IntegerDigits[p], 3] == {}, c++ ]]; Print[c]; p--, {n, 1, 8}] (from Robert G. Wilson v Feb 02 2004)
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CROSSREFS
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a(n) + A091647(n) = A006880(n).
Cf. A091634, A091635, A091636, A091638, A091639, A091640, A091641, A091642, A091643.
Sequence in context: A009151 A009007 A000949 this_sequence A074542 A105622 A110903
Adjacent sequences: A091634 A091635 A091636 this_sequence A091638 A091639 A091640
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KEYWORD
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more,nonn,base
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AUTHOR
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Enoch Haga (Enokh(AT)comcast.net), Jan 30 2004
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EXTENSIONS
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Edited and extended by Robert G. Wilson v (rgwv(AT)rgwv.com), Feb 02 2004
a(9)-a(12) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Feb 14 2008
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