|
Search: id:A143702
|
|
| |
|
| 6, 14, 30, 30, 42, 30, 78, 182, 1110, 570, 1830, 6666, 2310, 2534, 5538, 9870, 20010, 141270, 14070, 480090, 155490, 334110, 1794858, 2463270, 2132130, 2349390
(list; graph; listen)
|
|
|
OFFSET
|
1,1
|
|
|
COMMENT
|
Product of distinct prime divisors of (2^n)*a(n)*(2^n-a(n)) is called also radical: rad((2^n)*a(n)*(2^n-a(n))
For numbers a(n) see A143700
For numbers 2^n-a(n) see A143701
For minimal values of rad((2^n)*a(n)*(2^n-a(n)) see A143702 [Wrong A-number? - N. J. A. Sloane (njas(AT)research.att.com), Nov 13 2008]
For minimal values of rad(a(n)*(2^n-a(n)) see A143703
|
|
MATHEMATICA
|
a = {{1, 1}}; aa = {1}; bb = {1}; rr = {}; Do[logmax = 0; k = 2^x; w = Floor[(k - 1)/2]; Do[m = FactorInteger[n (k - n)]; rad = 1; Do[rad = rad m[[s]][[1]], {s, 1, Length[m]}]; log = Log[k]/Log[rad]; If[log > logmax, bmin = k - n; amax = n; logmax = log; r = rad], {n, 1, w, 2}]; Print[{x, amax}]; AppendTo[aa, amax]; AppendTo[bb, bmin]; AppendTo[rr, r]; AppendTo[a, {x, logmax}], {x, 2, 15}]; rr (*Artur Jasinski with assistance of Maximilian Hasler*)
|
|
CROSSREFS
|
Cf. A007947, A085152, A085153, A147298-A147307, A147638-A147643.
Sequence in context: A063590 A128806 A139596 this_sequence A134067 A024932 A078836
Adjacent sequences: A143699 A143700 A143701 this_sequence A143703 A143704 A143705
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Artur Jasinski (grafix(AT)csl.pl), Nov 10 2008
|
|
|
Search completed in 0.002 seconds
|
