1800748domain: NAppears in sequencesNumber of (n+6)X(n+6) 0..2 matrices with each 7X7 subblock idempotent.at n=2A224637Number of (n+6)X9 0..2 matrices with each 7X7 subblock idempotent.at n=2A224640T(n,k) = Number of (n+6) X (k+6) 0..2 matrices with each 7 X 7 subblock idempotent.at n=12A224642