OFFSET
0,4
COMMENTS
Similarly to A364027 the same number cannot occur four times in a row. In the first 10 million terms three consecutive equal numbers occurs twenty-three times, the last such triplet being a(8247993)..a(8247995) = 59. It is likely such triplets occur infinitely often although this is unknown.
LINKS
Scott R. Shannon, Table of n, a(n) for n = 0..10000.
Scott R. Shannon, Image of the first 10 million terms.
EXAMPLE
a(2) = 1 as there is one pair whose product equals a(0) * a(1) = 0, namely a(0) * a(1).
a(3) = 2 as a(1) * a(2) = 0 * 1 = 0, and there has been two previous pairs whose product is 0, namely a(0) * a(1) and a(1) * a(2).
a(11) = 4 as a(9) * a(10) = 1 * 2 = 2, and there has been four previous pairs whose product is 2, namely a(2) * a(3), a(3) * a(4), a(4) * a(5) and a(9) * a(10).
CROSSREFS
KEYWORD
nonn
AUTHOR
Scott R. Shannon, Jul 05 2023
STATUS
approved