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A282783
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Number of terms in A282430 less than or equal to 10^n.
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0
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0, 1, 1, 6, 77, 1069, 13041, 153389, 1691609, 18175623, 192338138
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OFFSET
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0,4
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COMMENTS
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An approximate value of a(n) is given by C*10^n*(exp(-2) - 1/log(10^n)), where C = 0.209.
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LINKS
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PROG
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(PARI) a(n)={t=0; forstep(m=2, 10^n, 2, if(!(m%3)==0, x=0; until(p<2||isprime(p), p=m-3^x; x++); if(p<2, t++))); return(t)};
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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