223736

Appears in sequences

• Tetranacci numbers: a(n) = a(n-1) + a(n-2) + a(n-3) + a(n-4), with a(0)=a(1)=0, a(2)=1, a(3)=2.at n=21A001630
• Composite numbers k such that sigma_2(k) - 1 is a square, where sigma_2(k) = A001157(k) is the sum of squares of divisors of k.at n=6A318169
• Number of palindromic binary strings of length n having no 4-runs of 1's.at n=38A382478