A092680 Numbers of the form 3*2^k with a single anti-divisor.

3, 6, 96, 393216

Offset

1,1

Comments

See A066272 for definition of anti-divisor.

If it exists, a(5) > 3*2^(1000). See A092679. - J.W.L. (Jan) Eerland, Nov 13 2022

Links

Table of n, a(n) for n=1..4.

Formula

a(n) = 3*2^A092679(n).

Prog

(Python)
from itertools import count, islice
from sympy.ntheory.factor_ import antidivisor_count
def A092680_gen(): return filter(lambda n: antidivisor_count(n)==1, (3*2**k for k in count(0)))
A092680_list = list(islice(A092680_gen(), 4)) # Chai Wah Wu, Jan 04 2022

Crossrefs

Cf. A066272, A066466, A092679.

Sequence in context: A299433 A036286 A084008 * A101574 A082980 A157536

Adjacent sequences: A092677 A092678 A092679 * A092681 A092682 A092683

Keyword

nonn,hard,more

Author

Lior Manor, Mar 03 2004

Status

approved