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.

Showing 1-3 of 3 results.

A192229 Indices of records in A087669.

Original entry on oeis.org

1, 2, 3, 5, 10, 11, 17, 23, 31, 47, 59, 71, 107, 151, 167, 239, 367, 421, 569, 587, 653, 701, 733, 857, 1063, 1229, 1693, 2003, 2141, 2273, 2531, 2549, 3181, 3547, 3919, 4703, 5437, 5659, 6379, 7841, 8093, 8209, 9001, 13313
Offset: 1

Views

Author

Max Alekseyev, Jun 26 2011

Keywords

Comments

Conjecture: the terms starting with 11 are prime.
Records are given by A192230.

Crossrefs

Cf. A087669, A192230, A086336, A087663, A087666

A192230 Records in A087669.

Original entry on oeis.org

0, 1, 3, 5, 9, 19, 27, 32, 78, 106, 108, 156, 367, 509, 542, 1155, 1158, 1172, 1262, 1268, 1428, 1738, 2497, 2868, 3989, 6018, 6452, 8010, 8178, 10537, 10870, 11434, 13915, 15370, 20685, 20852, 22854, 29415, 32406, 35779, 40456, 43938, 48568, 84406
Offset: 1

Views

Author

Max Alekseyev, Jun 26 2011

Keywords

Crossrefs

Cf. A087669, A192229, A086336, A087663, A087666

Formula

a(n) = A087669(A192229(n))

A087670 The first integer in the sequence defined by b(0)=(2n+1)/n and b(k+1)=b(k)*floor(b(k)) for k>=0.

Original entry on oeis.org

3, 5, 336, 18, 8003163168, 86632, 7191948600, 17, 72960
Offset: 1

Views

Author

N. J. A. Sloane, Sep 27 2003

Keywords

Comments

a(10) ~= 2.767*10^155 is too large to show here.
It is conjectured that an integer is always reached if the initial value is >= 2.

Links

  • J. C. Lagarias and N. J. A. Sloane, Approximate squaring (pdf, ps), Experimental Math., 13 (2004), 113-128.

Crossrefs

Cf. A087669 (steps to reach an integer), A087666.
Showing 1-3 of 3 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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