|
|
A337643
|
|
a(1) = 1; thereafter a(n) = a(n-1) / lpf(n) if lpf(n) divides a(n-1), otherwise a(n) = a(n-1) * lpf(n), where lpf is the least prime factor function A020639.
|
|
0
|
|
|
1, 1, 2, 6, 3, 15, 30, 210, 105, 35, 70, 770, 385, 5005, 10010, 30030, 15015, 255255, 510510, 9699690, 4849845, 1616615, 3233230, 74364290, 37182145, 7436429, 14872858, 44618574, 22309287, 646969323, 1293938646, 40112098026, 20056049013, 6685349671, 13370699342
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,3
|
|
LINKS
|
|
|
MAPLE
|
A020639 := proc(n) if n = 1 then 1; else min(op(numtheory[factorset](n))) ; end if; end proc:
a:=[1]; t:=1;
for n from 2 to 50 do
if (t mod u) = 0 then t:=t/u else t:=t*u; fi; a:=[op(a), t];
od;
a;
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|