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A064489
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Let p = prime(n); a(n) = smallest m such that prime(m) has p digits.
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2
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OFFSET
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1,1
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LINKS
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Table of n, a(n) for n=1..9.
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EXAMPLE
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n=5; prime(5)=11 and 11 is the first prime with a prime number of decimal digits.
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PROG
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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(n))))
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CROSSREFS
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Cf. A064490.
a(n) = 1 + A006880(A000040(n-1)).
Sequence in context: A226125 A132509 A281747 * A081089 A180928 A118391
Adjacent sequences: A064486 A064487 A064488 * A064490 A064491 A064492
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KEYWORD
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base,easy,nonn
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AUTHOR
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Jason Earls, Oct 04 2001
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EXTENSIONS
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More terms from David Wasserman, Jul 22 2002
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STATUS
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approved
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