419878

Appears in sequences

• Number of (n+3)X(2+3) 0..3 black square subarrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, and upper left element zero.at n=5A231020
• Number of (n+3)X(6+3) 0..3 black square subarrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, and upper left element zero.at n=1A231022
• T(n,k)=Number of (n+3)X(k+3) 0..3 black square subarrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, and upper left element zero.at n=22A231023
• T(n,k)=Number of (n+3)X(k+3) 0..3 black square subarrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, and upper left element zero.at n=26A231023
• a(0) = 1; a(n) = Sum_{k=1..n} gcd(n,k)*a(n-k).at n=16A308445