49259domain: NAppears in sequencesa(n) = (12*n+1)*(12*n+11).at n=18A001538Number of 5-dimensional centered tetrahedral numbers.at n=15A008499a(0)=2. a(n) = the a(n-1)th integer from among those positive integers coprime to n.at n=20A125554a(n) = Sum_{k=0..n} binomial(3*n+k,n).at n=5A387117