login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A147300 a(n) = smallest value of parameter m such that function rad(m n (n - m)) have minimal value n=2,3,4..., 0 < m < n where function rad(k) called also radical(k) is product distinct prime divisors of k. 10
1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 7, 1, 1, 1, 2, 1, 2, 1, 4, 5, 1, 9, 3, 1, 1, 11, 7, 1, 9, 1, 16, 1, 1, 1, 2, 1, 1, 1, 1, 25, 4, 5, 1, 1, 25, 9, 27, 1, 1, 1, 1, 1, 1, 1, 3, 1, 5, 1, 7, 1, 1, 25, 11, 1, 13, 1, 4, 1, 1, 1, 2, 1, 4, 5, 23, 7, 8, 1, 27, 11, 1, 13, 14, 1, 1, 17, 1, 1 (list; graph; refs; listen; history; internal format)
OFFSET

2,10

COMMENTS

Function rad(k) is used in ABC conjecture applications.

For smallest values of function rad(m n (n - m)) see A147298

For biggest values of function rad(m n (n - m)) see A147299

For numbers m for which rad(m n (n - m)) reached minimal value see A147300

For numbers m for which rad(m n (n - m)) reached maximal value see A147301

Sequence in each value Log[n]/Log[A147298(n)] reached records see A147302

MATHEMATICA

logmax = 0; aa = {}; bb = {}; cc = {}; dd = {}; ee = {}; ff = {}; gg \ = {}; Do[min = 10^100; max = 0; ile = 0; Do[If[GCD[m, n, n - m] == 1, ile = ile + 1; s = m n (n - m); k = FactorInteger[s]; g = 1; Do[g = g k[[p]][[1]], {p, 1, Length[k]}]; If[g > max, max = g; mmax = m]; If[g < min, min = g; mmin = m]], {m, 1, n - 1}]; AppendTo[aa, min]; AppendTo[bb, max]; AppendTo[cc, mmax]; AppendTo[dd, mmin]; AppendTo[gg, ile]; If[(Log[n]/Log[min]) > logmax, logmax = (Log[n]/Log[min]); AppendTo[ee, {N[logmax], n, mmin, min, mmax, max}]; Print[{N[logmax], n, mmin, min, mmax, max}]; AppendTo[ff, n]], {n, 2, 129}]; dd (*Artur Jasinski*)

CROSSREFS

A085152, A085153, A147298-A147307.

Sequence in context: A086251 A177121 A092931 * A110503 A030556 A030575

Adjacent sequences:  A147297 A147298 A147299 * A147301 A147302 A147303

KEYWORD

nonn

AUTHOR

Artur Jasinski (grafix(AT)csl.pl), Nov 05 2008

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 16 10:32 EST 2012. Contains 205904 sequences.