1393455826

Appears in sequences

• a(1) = 1, then subtract, add, and multiply 2, 3, 4; 5, 6, 7; ... in that order.at n=26A362269
• a(n) = (3*n-2)!!! * Sum_{k=0..n} 1/(3*k-2)!!!.at n=9A368790