|
| |
| |
|
|
|
0, 1, 2, 2, 3, 3, 5, 5, 6, 5, 5, 6, 7, 7, 10, 10, 7, 7, 13, 10, 10, 11, 13, 13, 14, 13, 13, 14, 14, 15, 14, 15, 19, 17, 14, 19, 15, 19, 17, 19, 19, 21, 21, 22, 23, 23, 26, 26, 23, 29, 29, 26, 23, 23, 26, 26, 26, 29, 29, 30, 30, 31, 33, 33, 31, 33, 33, 34, 34, 35, 34, 35, 38, 37, 38, 38, 38, 39, 38, 41, 39, 41, 41, 42, 42, 43, 41, 46, 46, 47, 38, 46, 46, 47
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,3
|
|
|
COMMENTS
|
After the initial zero, all terms are squarefree numbers (A005117).
|
|
|
LINKS
|
|
|
|
FORMULA
|
|
|
|
PROG
|
(Python)
from sympy.ntheory.factor_ import core
def issquarefree(n): return core(n) == n
def a285734(n):
if n==1: return 0
j=n//2
while True:
if issquarefree(j) and issquarefree(n - j): return j
else: j-=1
def a285735(n): return n - a285734(n)
def a286105(n): return 0 if n==1 else 1 + max(a286105(a285734(n)), a286105(a285735(n)))
def a286106(n): return 0 if n==1 else a286105(a285735(n)) - a286105(a285734(n))
def a286107(n): return 0 if n==1 else a285735(n) if a286106(n)>0 else a285734(n)
print([a286107(n) for n in range(1, 121)]) # Indranil Ghosh, May 02 2017
|
|
|
CROSSREFS
|
|
|
|
KEYWORD
|
nonn
|
|
|
AUTHOR
|
|
|
|
STATUS
|
approved
|
| |
|
|
