51751

Appears in sequences

• a(n) = n^4 + 5*n^2 + 1.at n=15A082113
• E.g.f.: exp(1-sqrt(1-2*x-4*x^2)).at n=6A144576
• Numerators of expansion of exp(1-sqrt(1-x-x^2)).at n=6A144579
• Number of n X n symmetric binary arrays with rows, considered as binary numbers, in strictly increasing order, and no more than 3 ones in any row.at n=7A162093
• Number of triangular n X n X n arrays colored with integers 0 upwards introduced in row major order, with no element equal to any neighbor, and containing the value n(n+1)/2-2.at n=24A211899
• G.f.: Product_{k>=1} (1 + x^k) / (1 - x^(k*(k+1)/2)).at n=40A280422