A055723 Number of lucky numbers (A000959) <= 10^n.

1, 4, 23, 153, 1118, 8772, 71918, 609237, 5286238, 46697909, 418348044, 3790060378, 34652117969, 319239995375, 2960006060823, 27596305747873

Offset

0,2

Comments

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.

Links

Table of n, a(n) for n=0..15.

W. Schneider, Lucky Numbers

Eric Weisstein's World of Mathematics, Lucky Numbers

Mathematica

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 *)

Crossrefs

Cf. A000959, A006880.

Sequence in context: A192730 A246813 A369213 * A364478 A271469 A366070

Adjacent sequences: A055720 A055721 A055722 * A055724 A055725 A055726

Keyword

base,more,nonn

Author

Robert G. Wilson v, Jun 09 2000

Extensions

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

a(10) from Robert G. Wilson v, Oct 16 2010

a(11)-a(15) from Hiroaki Yamanouchi, May 07 2015

Status

approved