136052736
domain: N
Appears in sequences
- Number of (n+2) X (7+2) 0..3 arrays with every 3 X 3 subblock row and column sum equal to 0 2 3 6 or 7 and every 3 X 3 diagonal and antidiagonal sum not equal to 0 2 3 6 or 7.at n=18A252113
- a(1) = 1, a(2) = 3; for n > 1, a(n) = sum of the next two smallest integers > a(n-1) which are coprime to the sum s = a(1) + ... + a(n-1).at n=25A308669