58201641domain: NAppears in sequencesa(n+1) is the smallest square > a(n) such that every concatenation (n > 1) is a prime.at n=27A087352Number of 6Xn 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 0 1 and 0 1 1 vertically.at n=9A207126