login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A349228 Products of three consecutive terms of A349227: a(n) = A349227(n) * A349227(n+1) * A349227(n+2). 2
1, 2, 4, 8, 12, 6, 3, 5, 10, 20, 16, 24, 36, 9, 15, 25, 50, 30, 18, 27, 45, 60, 40, 32, 48, 72, 54, 63, 21, 7, 11, 22, 44, 28, 14, 35, 55, 110, 66, 42, 84, 56, 64, 80, 120, 75, 90, 150, 180, 210, 126, 105, 135, 225, 270, 240, 96, 112, 70, 140, 100, 160, 200 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
All terms are distinct.
Is this sequence a permutation of the natural numbers?
LINKS
EXAMPLE
a(5) = A349227(5) * A349227(6) * A349227(7) = 2 * 2 * 3 = 12.
PROG
(PARI) s=0; pp=p=1; for (n=1, 63, for (v=1, oo, if (!bittest(s, q=pp*p*v), print1 (q", "); s+=2^q; pp=p; p=v; break)))
(Python)
def aupton(terms):
A349227lst, plst, pset = [1, 1], [], set()
for n in range(terms):
p = p2 = A349227lst[-1]*A349227lst[-2]
while p in pset: p += p2
A349227lst.append(p//p2); plst.append(p); pset.add(p)
return plst
print(aupton(63)) # Michael S. Branicky, Nov 12 2021
CROSSREFS
Sequence in context: A246703 A079389 A324991 * A337181 A357806 A051165
KEYWORD
nonn
AUTHOR
Rémy Sigrist, Nov 11 2021
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 28 05:02 EDT 2024. Contains 371235 sequences. (Running on oeis4.)