232566domain: NAppears in sequencesNumbers m such that N = (am+1)(bm+1)(cm+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,55.at n=26A065696a(n) = Floor[1/2((1-2/Sqrt[3])^n+(1-2/Sqrt[3])^n)].at n=17A116953a(n) = (1/4)*(n^2 - 2*n)^2 + (9/4)*(n^2 - 2*n) + 6.at n=31A294070