1844164

Appears in sequences

• Squares which are palindromes in base 3.at n=26A029985
• G.f.: (108*x^2+27*x+1)/(1+2*x-6*x^2-27*x^3).at n=11A103645
• Square array T(M,N) read by antidiagonals: number of dimer tilings of a 2M x 2N Klein bottle.at n=31A103999
• Square array T(M,N) read by antidiagonals: number of dimer tilings of a 2M x 2N Klein bottle.at n=38A103999
• a(1)=3 and a(n)=Floor[1/(n-1)^2 * a(n-1)^2].at n=7A176163