10864213579domain: NAppears in sequencesPendulum numbers: alternately append n to beginning or end of previous term.at n=9A053063Concatenate the decimal numbers n n-2 n-4 ...5 3 1 2 4 ... n-5 n-3 n-1 if n is odd, or n n-2 n-4 ... 6 4 2 1 3 5 ... n-5 n-3 n-1 if n is even.at n=9A281254