18338

Appears in sequences

• Least positive integer multiples of angle x such that their direction cosines form a unit vector: Sum_{k>0} cos(a(k)*x)^2 = 1, where a(1)=1, a(n+1)>a(n) and x=3-Pi/2.at n=24A080139
• Inverse permutation to A253561: a(n) = A252752(A122111(n)).at n=37A253562
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 54", based on the 5-celled von Neumann neighborhood.at n=36A270024
• Number of pairs (y, v), where y is a partition of n and v is a sub-multiset of y whose cardinality equals the number of distinct parts in y.at n=25A355383