760410domain: NAppears in sequencesNumbers k such that 11^k == -1 (mod k-1).at n=25A055694Number of (1+1) X (n+1) arrays of permutations of 0..n*2+1 with each element having directed index change 0,0 0,2 1,0 or -1,-2.at n=17A264365a(n) = p*(p - 1)*(13*p - 5)/6, where p = prime(n).at n=19A273221