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A308751
a(n) = (2 + Sum_{k = 1..n-1} A095258(k)) / A095258(n).
1
2, 1, 3, 2, 2, 2, 1, 3, 9, 16, 5, 3, 2, 17, 9, 24, 10, 25, 22, 13, 46, 7, 4, 2, 47, 45, 23, 16, 16, 3, 2, 17, 51, 72, 26, 9, 73, 111, 160, 49, 46, 5, 47, 72, 20, 146, 63, 112, 28, 113, 174, 95, 80, 63, 54, 160, 46, 11, 47, 72, 14, 12, 73, 130, 37, 131, 152, 51
OFFSET
1,1
COMMENTS
Are there infinitely many 1's in this sequence?
LINKS
EXAMPLE
a(3) = (2 + A095258(1) + A095258(2)) / A095258(3) = (2 + 1 + 3) / 2 = 3.
PROG
(PARI) See Links section.
(Python)
from itertools import islice
from sympy import divisors
def A308751_gen(): # generator of terms
bset, s = {1}, 3
yield 2
while True:
for d in divisors(s):
if d not in bset:
yield s//d
bset.add(d)
s += d
break
A308751_list = list(islice(A308751_gen(), 30)) # Chai Wah Wu, Jan 25 2022
CROSSREFS
Cf. A095258.
Sequence in context: A286364 A084216 A347240 * A057514 A377168 A273568
KEYWORD
nonn,look
AUTHOR
Rémy Sigrist, Jun 22 2019
STATUS
approved