OFFSET
1,2
COMMENTS
Parity of n and its sum of prime factors differs (counted with multiplicity). - The original name.
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..10000
FORMULA
{k | k+A001414(k) == 1 mod 2}. - Antti Karttunen, Jan 16 2023
EXAMPLE
111 = 3 * 37 -> sum = 40 so 111 is odd while 40 is even.
PROG
(PARI) isA036347(n) = A359768(n); \\ Antti Karttunen, Jan 15 2023
(Python)
from itertools import count, islice
from functools import reduce
from operator import ixor
from sympy import factorint
def A036347_gen(startvalue=1): # generator of terms
return filter(lambda n:(reduce(ixor, (p*e for p, e in factorint(n).items()), 0)^n)&1, count(max(startvalue, 1)))
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, Dec 15 1998
EXTENSIONS
Missing initial term a(1) = 1 prepended, offset corrected, name edited and more terms added by Antti Karttunen, Jan 15 2023
STATUS
approved