A092871 -id:A092871 - cp's OEIS frontend

A065894 Number of composites <= 10^n.

0, 5, 74, 831, 8770, 90407, 921501, 9335420, 94238544, 949152465, 9544947488, 95881945186, 962392087981, 9653934463160, 96795058249197, 970155429577330, 9720761658966074, 97376442842345766, 975260045712259139, 9765942332723655392, 97779180397439081159

Offset: 0

Labos Elemer, Nov 28 2001

nonn

Also, the order number of 10^n as a composite number.

			10 is the 5th composite number: 4, 6, 8, 9, 10.

Amiram Eldar, Table of n, a(n) for n = 0..29 (calculated using the b-file at A006880)

Cf. A002808, A006880, A092871.

Table[ 10^n- (PrimePi[10^n]) -1, {n, 1, 13} ]

a(n) = 10^n - 1 - A006880(n). - Max Alekseyev, Aug 15 2013

For n>0, a(n) = A092871(n) + 1.

More terms from Robert G. Wilson v, Nov 29 2001

Formula and more terms from Max Alekseyev, Aug 15 2013

A092853 Number of composites > mean composite (=A092802(n)) below 10^n.

Original entry on oeis.org

2, 37, 418, 4398, 45288, 461339, 4671939, 47150884, 474823446, 4774453663, 47957215384, 481331669604, 4828116680970, 48407394207052, 485163305702187

Offset: 1

Enoch Haga, Mar 07 2004

			At 10^1 there are 4 composites: 4+6+8+9=27. The rounded mean is 27\4=7. there are 2 composites over 7: 8 and 9, so a(1)=2.

Cf. A092802, A092853, A092854.

a(n) = A092871(n) - A092852(n) = A065894(n) - 1 - A092852(n). - Max Alekseyev, Aug 15 2013

Terms a(9)-a(15) from Max Alekseyev, Aug 15 2013

cp's OEIS Frontend

A065894 Number of composites <= 10^n.

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