A055723 - OEIS

%I #23 May 07 2015 12:05:40

%S 1,4,23,153,1118,8772,71918,609237,5286238,46697909,418348044,

%T 3790060378,34652117969,319239995375,2960006060823,27596305747873

%N Number of lucky numbers (A000959) <= 10^n.

%C As the two links show, lucky numbers possess a number of characteristics that are similar to those of the primes. This stems from the fact that both are the result of a sieving process. See A006880.

%H W. Schneider, <a href="http://web.archive.org/web/2004/www.wschnei.de/number-theory/lucky-numbers.html">Lucky Numbers</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/LuckyNumber.html">Lucky Numbers</a>

%t lst = Range[1, 10^6, 2]; i = 2; While[ i <= (len = Length@lst) && (k = lst[[i]]) <= len, lst = Drop[lst, {k, len, k}]; i++ ]; Table[ Length@ Select[t, #<=10^n &], {n, 8}] (* _Robert G. Wilson v_ *)

%Y Cf. A000959, A006880.

%K base,more,nonn

%O 0,2

%A _Robert G. Wilson v_, Jun 09 2000

%E a(8),a(9) were calculated by Walter Schneider (wschnei(AT)t-online.de).

%E a(10) from _Robert G. Wilson v_, Oct 16 2010

%E a(11)-a(15) from _Hiroaki Yamanouchi_, May 07 2015