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A355606
The indices where A354606(n) = 1.
1
1, 2, 4, 9, 14, 25, 37, 57, 99, 133, 182, 191, 404, 469, 595, 640, 780, 1195, 1884, 2407, 2808, 3010, 3217, 3444, 4245, 4383, 5773, 8703, 10069, 10731, 12640, 14470, 17998, 18535, 22648, 23341, 24286, 27431, 33702, 37019, 45593, 53759, 56598, 57578, 76640, 96729, 99557, 106881, 125900, 144162
OFFSET
1,2
COMMENTS
See A354606 for further details.
PROG
(Python)
from sympy import divisor_count
from collections import Counter
from itertools import count, islice
def f(n): return divisor_count(n)
def agen():
n, an, fan, inventory = 1, 1, 1, Counter([1])
yield n
for n in count(2):
an = inventory[fan]
fan = f(an)
inventory.update([fan])
if an == 1: yield n
print(list(islice(agen(), 50))) # Michael S. Branicky, Jul 09 2022
CROSSREFS
Sequence in context: A119637 A169762 A291465 * A227377 A341959 A173407
KEYWORD
nonn
AUTHOR
Scott R. Shannon, Jul 09 2022
STATUS
approved