210226

Appears in sequences

• Expansion of (2+x+3*x^2+2*x^3+x^4)/(1-x-5*x^2+x^3+3*x^4-x^5).at n=12A072684
• Number of squares in triangle-shaped polyominoes obtained by adding three identical polyominoes to the previous one, starting with one L-tetromino.at n=9A282389