|
|
A188348
|
|
Distance between n and the next number with the same number of distinct prime factors.
|
|
1
|
|
|
1, 1, 1, 2, 4, 1, 1, 2, 2, 2, 2, 3, 1, 3, 1, 2, 2, 4, 1, 1, 2, 2, 2, 2, 2, 2, 5, 2, 12, 1, 5, 1, 1, 1, 2, 4, 1, 1, 4, 2, 18, 4, 1, 1, 2, 2, 2, 4, 1, 1, 2, 6, 1, 1, 1, 1, 4, 2, 6, 3, 1, 2, 3, 3, 4, 4, 1, 3, 8, 2, 2, 6, 1, 1, 1, 3, 6, 2, 2, 2, 3, 6, 6, 1, 1, 1, 3, 8, 12
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
2,4
|
|
LINKS
|
|
|
FORMULA
|
|
|
MAPLE
|
N:= 200: # to use numbers up to N
V:= Array(2..N, n -> nops(numtheory:-factorset(n))):
A:= Array(2..N):
for n from 2 to N do
v:= V[n];
if assigned(Last[v]) then
A[Last[v]]:= n-Last[v]
fi;
Last[v]:= n;
od:
m:= min(select(t -> A[t]=0, [$2..N]))-1:
|
|
PROG
|
(PARI) for(n=2, 100, f=omega(n); m=n+1; while(omega(m)!=f, m++); print1(m-n, ", ")) \\ Colin Barker, Jun 27 2014
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
EXTENSIONS
|
Renamed, edited and checked by R. J. Mathar, Mar 28 2011.
|
|
STATUS
|
approved
|
|
|
|