338776

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 and x=2/3.at n=33A080140
• a(n) = Sum_{k=0..n+1}(binomial(n-1,k)/(k+1)*binomial(n+k+1,n-k)).at n=10A262441