446775310800domain: NAppears in sequencesBinomial coefficients C(2n, n-2).at n=19A002694Binomial coefficient C(42,n).at n=19A010958a(n) = binomial(n,19).at n=23A010972Binomial coefficient C(n,23).at n=19A010976T(2n+4,n), array T as in A050186; a count of aperiodic binary words.at n=19A051197