%I #8 Feb 28 2017 22:57:52
%S 0,1,1,6,77,1069,13041,153389,1691609,18175623,192338138
%N Number of terms in A282430 less than or equal to 10^n.
%C An approximate value of a(n) is given by C*10^n*(exp(-2) - 1/log(10^n)), where C = 0.209.
%o (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)};
%Y Cf. A282430.
%K nonn,more
%O 0,4
%A _Arkadiusz Wesolowski_, Feb 21 2017
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