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A268811 Sequence of positive integers where each is chosen to be as small as possible subject to the condition that no three terms a(j), a(j+k), a(j+2k) (for any j and k) form a geometric progression. 3
1, 1, 2, 1, 1, 2, 2, 3, 3, 1, 1, 2, 1, 1, 2, 2, 3, 3, 2, 3, 3, 5, 5, 6, 5, 5, 6, 1, 1, 2, 1, 1, 2, 2, 3, 3, 1, 1, 2, 1, 1, 2, 2, 3, 3, 2, 3, 3, 5, 5, 6, 5, 5, 6, 2, 3, 3, 5, 5, 6, 5, 5, 6, 6, 7, 7, 6, 7, 7, 8, 8, 10, 6, 7, 7, 6, 7, 7, 8, 8, 10, 1, 1, 2, 1, 1, 2, 2, 3, 3, 1, 1, 2, 1, 1, 2, 2, 3, 3, 2, 3, 3, 5, 5, 6, 5, 5, 6, 1, 1, 2, 1, 1, 2, 2, 3, 3, 1, 1, 2, 1, 1, 2, 2, 3, 3, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
COMMENTS
Apparently: all terms belong to A000452, and for any k > 0, the value A000452(k) first appears at index A265316(k+1). - Rémy Sigrist, May 13 2021
LINKS
Rémy Sigrist, C program for A268811
PROG
(Python)
A268811_list = []
for n in range(1000):
....i, j, b = 1, 1, set()
....while n-2*i >= 0:
........b.add(A268811_list[n-i]**2/A268811_list[n-2*i])
........i += 1
........while j in b:
............b.remove(j)
............j += 1
....A268811_list.append(j)
(C) See Links section.
CROSSREFS
Sequence in context: A029261 A359384 A100480 * A351192 A306460 A317805
KEYWORD
nonn,easy
AUTHOR
STATUS
approved

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Last modified May 23 15:23 EDT 2024. Contains 372763 sequences. (Running on oeis4.)