cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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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

Views

Author

Enoch Haga, Mar 07 2004

Keywords

Examples

			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.

Crossrefs

Cf. A092802, A092853, A092854.

Formula

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

Extensions

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

A092852 Number of composites <= A092802(n).

Original entry on oeis.org

2, 36, 412, 4371, 45118, 460161, 4663480, 47087659, 474329018, 4770493824, 47924729801, 481060418376, 4825817782189, 48387664042144, 484992123875142, 4859631205206357, 48681601698828085, 487571138851821274, 4882443976989269954, 48884842829781286250, 489393391263430721900
Offset: 1

Views

Author

Enoch Haga, Mar 07 2004

Keywords

Examples

			Up to 10^1 there are 4 composites: 4 + 6 + 8 + 9 = 27. The rounded mean is A092802(1) = floor(27/4) = 7. There are 2 composites below 7: 4 and 6, so a(1) = 2.

Crossrefs

Cf. A000720, A062298, A065855, A092802, A092853, A092854.

Formula

a(n) = A065855(A092802(n)) = A062298(A092802(n)) - 1 = A092802(n) - A000720(A092802(n)) - 1.

Extensions

a(9)-a(15) from Max Alekseyev, Aug 14 2013
a(16)-a(21) calculated using Kim Walisch's primecount and added by Amiram Eldar, Sep 05 2024
Showing 1-2 of 2 results.

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