209920

Appears in sequences

• a(n) = (6^n - (-2)^n)/8.at n=8A053524
• Number of quasi-triominoes in an n X n bounding box.at n=33A094170
• Numbers k such that k and k^2 use only the digits 0, 2, 4, 6 and 9.at n=33A136905
• Numbers n such that phi(n)/n = 16/41.at n=30A176598
• Expansion of 1/(1-2*x^2-4*x^3). (2,4)-Padovan sequence.at n=19A176739
• Number of non-symmetric binary n X n matrices M over the reals such that M^2 is the transpose of M.at n=10A336174