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Search: id:A064490
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| A064490 |
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Smallest prime with number of decimal digits equal to n-th prime. |
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+0 4
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| 11, 101, 10007, 1000003, 10000000019, 1000000000039, 10000000000000061, 1000000000000000003, 10000000000000000000009, 10000000000000000000000000331, 1000000000000000000000000000057
(list; graph; listen)
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OFFSET
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1,1
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LINKS
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Harry J. Smith, Table of n, a(n) for n=1,...,75
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EXAMPLE
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11 is the first prime with 2 decimal digits. 101 is the first prime with 3 decimal digits.
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MAPLE
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for n from 1 to 20 do p := ithprime(n): for i from 10^(p-1) to 10^p do if isprime(i) then printf(`%d, `, i); break; fi: od: od:
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PROGRAM
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(PARI) l(n)=ln=0; while(n, n=floor(n/10); ln++); return(ln); a=0; for(n=1, 10^6, x=l(prime(n)); if(isprime(x), b=x; if(b>a, a=b; print(prime(n)))))
(PARI) { for (n=1, 75, p=prime(n); a=nextprime(10^(p - 1)); write("b064490.txt", n, " ", a) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Sep 16 2009]
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CROSSREFS
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Cf. A064489.
Sequence in context: A070854 A075767 A080176 this_sequence A080439 A098153 A020449
Adjacent sequences: A064487 A064488 A064489 this_sequence A064491 A064492 A064493
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KEYWORD
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base,easy,nonn
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AUTHOR
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Jason Earls (zevi_35711(AT)yahoo.com), Oct 04 2001
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EXTENSIONS
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More terms from James A. Sellers (sellersj(AT)math.psu.edu), Oct 08 2001
OFFSET changed from 0,1 to 1,1 by` Harry J. Smith (hjsmithh(AT)sbcglobal.net), Sep 16 2009
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