Search: id:A153450 Results 1-1 of 1 results found. %I A153450 %S A153450 1,2,6,54,6542,203280221 %N A153450 Number of primes <= 2^(2^n) = PiPrime(A001146) %H A153450 H. J. Smith, XICalc - Extra Precision Integer Calculator. %F A153450 a(n) = PiPrime(2^(2^n)) %e A153450 a(3) = 54 because 2^(2^3) = 256 and there are 54 primes <= 256. %o A153450 (Other) (XICalc) Pi(2^(2^n)); %Y A153450 A001146 %Y A153450 Sequence in context: A085078 A152543 A122593 this_sequence A084123 A074023 A000146 %Y A153450 Adjacent sequences: A153447 A153448 A153449 this_sequence A153451 A153452 A153453 %K A153450 nonn %O A153450 0,2 %A A153450 Harry J. Smith (hjsmithh(AT)sbcglobal.net), Dec 27 2008 Search completed in 0.001 seconds