6317101910domain: NAppears in sequencesNumbers k such that 10*k^2 + 9 is a square.at n=19A075836a(0) = 1, a(1) = 2; a(n+1) = 6*a(n) + a(n-1) for n>1.at n=13A179237a(n) = 6*a(n-2) + a(n-4), where a(0) = 2, a(1) = 8, a(2) = 13, a(3) = 49.at n=24A228469