%I #16 Aug 12 2022 09:24:07
%S 1,1,2,6,14,30,40,55,247,488,818,1652,4060,3754,15748,20161,20128,
%T 85861,159827,211265,620076,993084,1487646,2542051,12137774,28169497,
%U 32223531,87591110,232647749,379598603,877039442
%N Length of longest cycle in n-th row of A329278 (triangular numbers mod 2^n).
%H Mathematics Stack Exchange user joriki, <a href="https://math.stackexchange.com/q/3491781/121988">Why do the triangular numbers initially form long cycles mod 2^k?</a>
%e For n = 3, the third row of A329278 is [0, 1, 3, 6, 2, 7, 5, 4] (zero-indexed) which has cycle 2 -> 3 -> 6 -> 5 -> 7 -> 4 -> 2, a cycle of length a(3) = 6.
%Y Cf. A329278.
%K nonn
%O 0,3
%A _Peter Kagey_, Dec 30 2019