5225670

Appears in sequences

• a(n+1) = n*a(n) + a(n-1) with a(0)=1, a(1)=0.at n=11A001053
• a(n) = denominator of the continued fraction which has the positive integers which are <= n and are coprime to n as its terms. The terms are written in order from 1 for the integer part, to n-1 for the final term of the continued fraction.at n=10A127615
• Array t(n, k) = (k*(n-1) +2-k)*t(n-1, k) + k*t(n-2, k), with t(1, k) = 1, t(2, k) = 2, read by antidiagonals.at n=45A144446