750312domain: NAppears in sequencesNumber of (n+2)X9 binary matrices with every 3X3 block having exactly four 1's.at n=7A181261Number of compositions of odd natural numbers into 4 parts <= n.at n=34A191903a(n)/2^n is the expected value of the length of the longest palindromic suffix of a random length-n binary string.at n=16A320303