31810737420domain: NAppears in sequencesa(n) = binomial(2*n, n) mod binomial(2*n-2, n-1).at n=18A024483a(n) is the difference between maximal and central squarefree kernel numbers dividing values of {binomial(n,k)} or A001405(n), respectively.at n=37A048682a(n) = (n-1)*Catalan(n).at n=19A276666