login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A087675 Consider recurrence b(0) = (2n+1)/2, b(n) = b(0)*floor(b(n-1)); sequence gives first integer reached. 3
5, 35, 18, 814, 39, 390, 68, 72827, 105, 1449, 150, 31887, 203, 3596, 264, 27852510, 333, 7215, 410, 208464, 495, 12690, 588, 10561998, 689, 20405, 798, 744049, 915, 30744, 1040, 46620858503, 1173, 44091, 1314, 1950450, 1463, 60830, 1620, 121575329, 1785 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

LINKS

Robert Israel, Table of n, a(n) for n = 2..10000

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

FORMULA

The even-indexed terms are given by A007742.

MAPLE

f:= proc(n)

  local b0, b;

  b0:= (2*n+1)/2;

  b:= b0;

  do

    b:= b0*floor(b);

    if b::integer then return b fi

  od

end proc:

map(f, [$2..100]); # Robert Israel, Nov 25 2019

CROSSREFS

A001511 gives number of steps to reach an integer.

Cf. A001511, A081853, A085071, A057016.

Sequence in context: A095865 A199359 A199584 * A128044 A299529 A014632

Adjacent sequences:  A087672 A087673 A087674 * A087676 A087677 A087678

KEYWORD

nonn,look

AUTHOR

N. J. A. Sloane, following a suggestion of Bela Bajnok (bbajnok(AT)gettysburg.edu), Sep 27 2003

EXTENSIONS

Offset corrected by Robert Israel, Nov 25 2019

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified February 25 11:19 EST 2021. Contains 341606 sequences. (Running on oeis4.)