149149

Appears in sequences

• Double primes: concatenation of the n-th prime with itself.at n=34A176597
• Number of zero-sum nX3 -1..1 arrays with every element unequal to at most two horizontal and vertical neighbors.at n=5A202042
• Number of zero-sum nX6 -1..1 arrays with every element unequal to at most two horizontal and vertical neighbors.at n=2A202045
• T(n,k)=Number of zero-sum nXk -1..1 arrays with every element unequal to at most two horizontal and vertical neighbors.at n=30A202047
• T(n,k)=Number of zero-sum nXk -1..1 arrays with every element unequal to at most two horizontal and vertical neighbors.at n=33A202047
• Number of n-digit numbers that have exactly 3 divisors.at n=12A379566
• Numbers k such that s(k) = s(k+2), where s(k) is the sum of odd divisors of k (A000593).at n=23A387920